chore(release): bump to 0.30.0

Two commits landed after v0.29.0 and neither is reachable: every entry point
on this machine runs the version-pinned plugin cache, not the tree.

Minor rather than patch because the behaviour is EXTENDED, not merely
repaired - coord-count.sh and board.sh gained a new exit status (3, "the
world you named is not there"), and pre-state-line-guard.mjs gained
CLAUDE_STATE_MAX_LINES. Exit codes are a contract, and the installed cache
still runs the old one.

Version synced across all seven version-bearing files - plugin.json,
package.json, the README badge, and the four SKILL.md frontmatters - so
release-plugin.mjs's plugin.json == README-badge == target check passes.
The three remaining 0.29.0 mentions (CLAUDE.md:915, CLAUDE.md:960,
board.sh:1388) are historical prose about when things shipped and must keep
saying 0.29.0.

CHANGELOG covers BOTH unreleased commits, not just the newest: d8fdeaa's
five defects were one class - a failed measurement rendering as a
reassuring value - and the entry carries what that session found about
itself, that --plan's free-capacity test had to move from "$7 + 0" to a
string comparison against "0", because "?" coerces to 0 in arithmetic and
would have certified an UNMEASURED tree as free capacity. The defect
reappearing one layer down, wearing the fix as a disguise.

No tag and no catalog change: that is the catalog session's order, which
runs release-plugin.mjs to do the tag and the ref bump atomically. Doing
both here would take a decision on the catalog's behalf without its
context.

Suites verified under system bash 3.2, not Homebrew 5.3: coord 242, board
300, route 69, orders 110, guard 54; npm test 11/11.

Order 20260826T115026Z-998059640-from-.claude

CHANGELOG.md

@@ -5,6 +5,111 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [0.30.0] - 2026-08-26
+
+Two commits landed after `v0.29.0` and neither is reachable: every entry point
+on this machine runs the version-pinned plugin cache, not the tree. Minor
+rather than patch because the behaviour is EXTENDED, not merely repaired -
+`coord-count.sh` and `board.sh` gained a new exit status and the state-line
+guard gained an environment variable. Exit codes are a contract, and the
+installed cache still runs the old one.
+
+All five defects here are the same class: **a failed measurement rendering as
+a reassuring value** - a broken or uninstrumented query returning a
+positive-looking null, consumed as a fact about the world.
+
+### Fixed
+
+- **`coord-count.sh`: a mailbox root that does not exist was byte-identical to
+  one where nobody has pending mail** - zero lines on stdout, exit 0, nothing
+  on stderr. `board.sh` consumes that TSV. The contract is now three statuses:
+  0 = counted, 2 = usage error, **3 = mailbox root absent**. 3 rather than 2 on
+  purpose: 2 already means "you called me wrong" and this means "the world you
+  named is not there" - two different repairs, and a consumer that only ever
+  sees one integer cannot tell them apart. Both nonzero paths print NOTHING on
+  stdout, so neither can be mistaken for a count of zero. What the old
+  "always 0" claim protected is kept and made precise: no state OF THE MAILBOX
+  can produce a nonzero exit, so a SessionStart still cannot be failed by mail.
+  An existing-but-empty root stays a silent, clean 0, and the selftest pins
+  that silence as hard as it pins the failure.
+- **`coord-count.sh`'s header promised exit 0 unconditionally, and that was
+  already false** - `--exclude` with no value exited 2 - so the documented
+  contract contradicted code a reader could run. The header text is now pinned
+  by a check of its own: a doc line nothing tests is a doc line that drifts,
+  which is how this one drifted.
+- **`board.sh`: `git status --porcelain | wc -l` yields zero lines whether the
+  tree is CLEAN or git refused to answer**, so DRT printed **0** and every
+  reader took it as "nothing uncommitted here". Reachable, not theoretical:
+  discovery tests `.git` with `-e` so worktrees are found, and a worktree whose
+  parent checkout was deleted exits 128. The exit status is now the
+  discriminator and an unmeasured tree reads **`?`** - the same token
+  `coord-count.sh` already uses for an age it could not compute.
+
+  **The fix was worthless without its two awk consumers, and one of them is
+  the point:** `--plan`'s free-capacity test compared `$7 + 0`, and `"?"`
+  coerces to **0** in arithmetic - so an UNMEASURED tree would have been
+  certified as free capacity. That is the defect reappearing one layer down,
+  wearing the fix as a disguise. It now compares the field as a STRING against
+  exactly `"0"`; only a tree measured clean is clean. The SUM roll-up, where a
+  `?` would silently add 0, now NAMES the repos it could not add.
+- **`board.sh`: a scan root that does not exist was skipped in silence**, so a
+  typo in `--roots`, a moved home directory and a genuinely empty tree were one
+  single output with the denominator never reported. Every bad root is now
+  named on stderr; the exit status changes only when NO root was scanned at all
+  (**3**, for the same reason as above). A mix still exits 0 and still prints
+  the board - some repos really were scanned. This REPLACES an older assertion
+  reading `check "missing root is a clean no-op"`: the defect encoded as a
+  passing test, which is why nothing ever caught it. `brief-nightly.sh` needs
+  no change and gains from this - it already treats a nonzero `--brief` as
+  failure and keeps yesterday's briefing, so a mistyped root now preserves the
+  file instead of overwriting it with an empty render.
+
+### Added
+
+- **`CLAUDE_STATE_MAX_LINES` overrides the state-line guard's limit**, the same
+  kind of knob `CLAUDE_COORD_DIR` is for the mailbox root. As a bare constant
+  the limit forced every boundary fixture to hardcode the number the code
+  carried - two copies of one policy, both rewritten by hand the last time the
+  operator moved it (60 -> 120). It is **not** a bypass claim; this guard has
+  always been escapable by writing the file another way. The one thing it must
+  never do is silently fail to take effect, so an UNUSABLE value (`""`, `"0"`,
+  negatives, anything not made of digits) **denies with a message naming the
+  variable** instead of falling back to 120 - a caller who set it and got the
+  default anyway would be reading a limit that was never in force.
+
+### Changed
+
+- **The README's Install block is now fenced (` ```bash `)** while the rest of
+  the README keeps its indented blocks. The org-side D-census reported this
+  repo as the only plugin of 12 with no start command; the premise was
+  imprecise - the lines were present, indented - but the finding held, because
+  the machine-readable entry point keys on a fenced block and 10 of 11 sibling
+  plugin READMEs use one. Measured before and after: 11 of 11 now match. Only
+  the Install block was converted; the other 39 indented blocks were not
+  ordered changed and converting them would bury a two-line fix in a
+  whole-file diff.
+
+### Known gaps, stated rather than closed
+
+- `coord-inbox.sh:57` and `coord-order-inbox.sh:60/64` carry the identical
+  `[ -d "$COORD" ] || exit 0` shape that was fixed in `coord-count.sh`. The
+  denominator was measured, not estimated, and they were deliberately left
+  alone: they are the INJECTION path, their output is prose a session reads
+  rather than a TSV a program parses, and their contract really is "never fail
+  a SessionStart".
+- `board.sh` does not yet CONSUME `coord-count.sh`'s new exit 3. The signal
+  exists; the `HAVE_COUNT` machinery does not read it. Tracked as separate
+  work rather than widened into this release in silence.
+
+### Testing
+
+Suites at this release, verified under system bash 3.2 (not Homebrew 5.3):
+coord 242, board 300, route 69, orders 110, state-line-guard 54; `npm test`
+11/11. Every design choice above was mutation-tested, and every negative check
+carries a known-positive control - one selftest section's first cut was
+VACUOUSLY green (wrong basename, plus a fixture path that was never exported)
+and is recorded in `CLAUDE.md` rather than quietly fixed.
+
 ## [0.29.0] - 2026-08-23
 
 Answers a question the board could not answer before: which repos are finished