feat(ultraplan-local)!: v2.0.0 — brief-driven four-command pipeline

Extract interview from /ultraplan-local into new /ultrabrief-local command.
/ultraplan-local now requires --brief or --project (breaking). All pipeline
artifacts land in one project directory: .claude/projects/{date}-{slug}/
with brief.md, research/, plan.md, sessions/, progress.json.

Breaking changes:
- /ultraplan-local requires --brief <path> or --project <dir>
- /ultraplan-local --spec removed (convert specs to briefs per MIGRATION.md)
- Interview phase moved to /ultrabrief-local
- spec-reviewer renamed to brief-reviewer with 5th dimension (Research Plan validity)

Added:
- /ultrabrief-local command (interactive interview → brief.md with research plan)
- templates/ultrabrief-template.md (task brief format with intent + research plan)
- brief-reviewer agent (5-dimension brief quality review)
- --project <dir> flag on /ultraresearch-local, /ultraplan-local, /ultraexecute-local
- MIGRATION.md (v1 → v2 upgrade guide)

Changed:
- planning-orchestrator accepts Brief file: input (was Spec file:)
- planning-orchestrator Phase 1b uses brief-reviewer
- README + CLAUDE.md rewritten for four-command pipeline and task/research brief terminology
- CHANGELOG.md [2.0.0] entry with rationale
- Marketplace root README + CLAUDE.md updated to v2.0.0

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

plugins/ultraplan-local/commands/ultraresearch-local.md

@@ -1,7 +1,7 @@
 ---
 name: ultraresearch-local
 description: Deep research combining local codebase analysis with external knowledge, producing structured research briefs with triangulation and confidence ratings
-argument-hint: "[--quick | --local | --external | --fg] <research question>"
+argument-hint: "[--project <dir>] [--quick | --local | --external | --fg] <research question>"
 model: opus
 allowed-tools: Agent, Read, Glob, Grep, Write, Edit, Bash, AskUserQuestion, WebSearch, WebFetch, mcp__tavily__tavily_search, mcp__tavily__tavily_research
 ---
@@ -42,12 +42,24 @@ Supported flags:
 4. `--fg` — foreground mode. Run all phases inline (blocking) instead of
    launching the research-orchestrator in background. Set **execution = foreground**.
 
+5. `--project <dir>` — attach this research to an ultrabrief project folder.
+   The brief will be written to `{dir}/research/{NN}-{slug}.md` (auto-incremented
+   index) instead of the default `.claude/research/` path. Set **project_dir = {dir}**.
+
+   If `{dir}` does not exist:
+   ```
+   Error: project directory not found: {dir}
+   Run /ultrabrief-local first to create it.
+   ```
+   Create `{dir}/research/` if it does not already exist.
+
 Flags can be combined:
 - `--local --fg` — local-only research, foreground
 - `--external --quick` — external-only, lightweight
+- `--project <dir> --external` — attach external research to a project
 - `--quick` alone implies both local and external (lightweight)
 
-Defaults: **scope = both**, **execution = background**.
+Defaults: **scope = both**, **execution = background**, **project_dir = none**.
 
 After stripping flags, the remaining text is the **research question**.
 
@@ -59,6 +71,7 @@ Usage: /ultraresearch-local <research question>
        /ultraresearch-local --local <research question>
        /ultraresearch-local --external <research question>
        /ultraresearch-local --fg <research question>
+       /ultraresearch-local --project <dir> [--external|--local|--quick|--fg] <research question>
 
 Modes:
   default       Interview → background research (local + external) → brief
@@ -66,8 +79,9 @@ Modes:
   --local       Only codebase analysis agents (skip external + Gemini)
   --external    Only external research agents (skip codebase analysis)
   --fg          All phases in foreground (blocks session)
+  --project     Write brief into an ultrabrief project folder (auto-indexed)
 
-Flags can be combined: --local --fg, --external --quick
+Flags can be combined: --local --fg, --external --quick, --project <dir> --external
 
 Examples:
   /ultraresearch-local Should we migrate from Express to Fastify?
@@ -75,6 +89,7 @@ Examples:
   /ultraresearch-local --local How is error handling structured in this codebase?
   /ultraresearch-local --external What are the security implications of using Redis for sessions?
   /ultraresearch-local --fg --local What patterns does this codebase use for database access?
+  /ultraresearch-local --project .claude/projects/2026-04-18-jwt-auth --external What JWT library is best for Node.js?
 ```
 
 Do not continue past this step if no question was provided.
@@ -82,9 +97,23 @@ Do not continue past this step if no question was provided.
 Report the detected mode:
 ```
 Mode: {default | quick}, Scope: {both | local | external}, Execution: {background | foreground}
+Project: {project_dir or "-"}
 Question: {research question}
 ```
 
+### Compute brief destination
+
+If **project_dir is set**:
+- Scan `{project_dir}/research/` for existing files matching `NN-*.md`.
+- Find the highest existing index; set `N = highest + 1`. If no files exist, `N = 1`.
+- Zero-pad to 2 digits: `01`, `02`, ...
+- Brief destination: `{project_dir}/research/{NN}-{slug}.md`
+
+If **project_dir is not set**:
+- Brief destination: `.claude/research/ultraresearch-{YYYY-MM-DD}-{slug}.md`
+
+Store as `brief_destination` for use in later phases.
+
 ## Phase 2 — Research interview
 
 Use `AskUserQuestion` to clarify the research question. Ask **one question at a time**.
@@ -146,7 +175,7 @@ Research dimensions identified:
 **If execution = background (default):**
 
 Generate a slug from the research question (first 3-4 meaningful words, lowercase,
-hyphens).
+hyphens). Use the `brief_destination` computed in Phase 1.
 
 Launch the **research-orchestrator** agent with this prompt:
 
@@ -155,7 +184,8 @@ Research question: {question}
 Dimensions: {list of dimensions from interview}
 Mode: {default | quick}
 Scope: {both | local | external}
-Brief destination: .claude/research/ultraresearch-{YYYY-MM-DD}-{slug}.md
+Project dir: {project_dir or "-"}
+Brief destination: {brief_destination}
 Plugin root: ${CLAUDE_PLUGIN_ROOT}
 ```
 
@@ -168,7 +198,8 @@ Background research started via research-orchestrator.
   Question: {research question}
   Dimensions: {N} identified
   Scope: {both | local | external}
-  Brief: .claude/research/ultraresearch-{date}-{slug}.md
+  Project: {project_dir or "-"}
+  Brief: {brief_destination}
 
 You will be notified when the research brief is ready.
 You can continue working on other tasks in the meantime.
@@ -317,8 +348,11 @@ Write the research brief following the template. Key rules:
 6. **Sources** — every claim traced to URL or codebase path.
 
 Generate the slug from the research question (first 3-4 meaningful words).
-Write the brief to: `.claude/research/ultraresearch-{YYYY-MM-DD}-{slug}.md`
-Create the `.claude/research/` directory if needed.
+Write the brief to the `brief_destination` computed in Phase 1:
+- With `--project`: `{project_dir}/research/{NN}-{slug}.md`
+- Without `--project`: `.claude/research/ultraresearch-{YYYY-MM-DD}-{slug}.md`
+
+Create the parent directory if it does not exist.
 
 ## Phase 8 — Present and track
 
@@ -329,7 +363,8 @@ Present a summary to the user:
 
 **Question:** {research question}
 **Mode:** {default | quick}, Scope: {both | local | external}
-**Brief:** .claude/research/ultraresearch-{date}-{slug}.md
+**Brief:** {brief_destination}
+**Project:** {project_dir or "-"}
 **Confidence:** {overall confidence 0.0-1.0}
 **Dimensions:** {N} researched
 **Agents:** {N} local + {N} external + {gemini: used | unavailable | skipped}
@@ -346,8 +381,9 @@ Present a summary to the user:
 - {Question 1, or "None — all dimensions adequately covered."}
 
 You can:
-- Read the full brief at {brief path}
-- Feed into planning: `/ultraplan-local --research {brief path} <task>`
+- Read the full brief at {brief_destination}
+- If `--project` was used: run `/ultraplan-local --project {project_dir}` when all research topics are complete
+- Otherwise: `/ultraplan-local --research {brief_destination} --brief <your-brief.md>`
 - Ask follow-up questions about specific findings
 ```
 
@@ -364,6 +400,8 @@ Record format (one JSON line):
   "mode": "{default|quick}",
   "scope": "{both|local|external}",
   "slug": "{brief slug}",
+  "project_dir": "{project_dir or null}",
+  "brief_path": "{brief_destination}",
   "dimensions": {N},
   "agents_local": {N},
   "agents_external": {N},