feat(voyage)!: bulk content rewrite ultra -> voyage/trek prose [skip-docs]

Sed-pipeline (16 patterns, longest-match-first) sweeper residuelle ultra*-treff
i prose, command-narrativ, agent-prompts, hook-kommentarer, doc-prosa.

Pipeline-utvidelser fra V4-prompten:
- BSD-syntax [[:<:]]ultra[[:>:]] istedenfor \bultra\b (BSD sed mangler \b)
- 6 compound-patterns for ultraplan/ultraexecute/ultraresearch/ultrabrief/
  ultrareview/ultracontinue uten -local-suffiks
- ultra*-stats glob -> trek*-stats glob
- Linje-eksklusjon redusert til ultra-cc-architect (Q8); session-state-
  eksklusjonen var over-protektiv
- File-eksklusjon utvidet til settings.json, package.json, plugin.json,
  hele .claude/-treet (gitignored + V5-territorium)

Q8-undantak holdt: architecture-discovery.mjs + project-discovery.mjs urort.
Filnavn-konvensjon holdt: .session-state.local.json + *.local.* preservert.

Manuell narrative-fix: tests/lib/agent-frontmatter.test.mjs linje 10
mangled "/ultra*-local" til "/voyage*-local" (ingen slik kommando finnes);
korrigert til "/trek*".

Residualer utenfor scope (V5 handterer): package.json + .claude-plugin/
plugin.json (Step 12-14 versjons-bump). .claude/* er gitignored
spec-historikk med tilsiktet BEFORE/AFTER-narrativ.

Part of voyage-rebrand session 3 (Wave 4 / Step 10).

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

plugins/ultraplan-local/templates/trekreview-template.md

@@ -42,7 +42,7 @@ should look at first.
 - file: lib/foo.mjs
 - line: 42
 - rule_key: BROKEN_SUCCESS_CRITERION
-- brief_ref: SC3 — "review.md is parseable as input to /ultraplan-local"
+- brief_ref: SC3 — "review.md is parseable as input to /trekplan"
 - title: Plan-validator rejects review.md when source_findings is flow-style
 - detail: The validator at lib/validators/plan-validator.mjs:N reads
   `source_findings` via parseDocument(), which does not support flow-style
@@ -101,7 +101,7 @@ should look at first.
 - 1 MINOR → nice-to-have for v1.1
 - 1 SUGGESTION → log and move on
 
-If running `/ultraplan-local --brief review.md`, the planner will consume
+If running `/trekplan --brief review.md`, the planner will consume
 the BLOCKER + MAJOR findings as plan goals (their `recommended_action`
 becomes the step intent). MINOR + SUGGESTION are skipped for v1.0
 plan-input.