feat: v3.0.0 architecture overhaul

- Rename marketplace to lm-claude-plugins
- Move MCP servers to root with symlinks
- Add 6 PR tools to Gitea MCP (list_pull_requests, get_pull_request,
  get_pr_diff, get_pr_comments, create_pr_review, add_pr_comment)
- Add clarity-assist plugin (prompt optimization with ND accommodations)
- Add git-flow plugin (workflow automation)
- Add pr-review plugin (multi-agent review with confidence scoring)
- Centralize configuration docs
- Update all documentation for v3.0.0

BREAKING CHANGE: MCP server paths changed, marketplace renamed

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

plugins/pr-review/commands/pr-review.md

@@ -0,0 +1,139 @@
+# /pr-review - Full Multi-Agent Review
+
+## Purpose
+
+Conduct a comprehensive pull request review using specialized agents for security, performance, maintainability, and test coverage.
+
+## Usage
+
+```
+/pr-review <pr-number> [--repo owner/repo]
+```
+
+## Behavior
+
+### Step 1: Fetch PR Data
+
+Using Gitea MCP tools:
+1. `get_pull_request` - PR metadata
+2. `get_pr_diff` - Code changes
+3. `get_pr_comments` - Existing discussion
+
+### Step 2: Dispatch to Agents
+
+The coordinator dispatches review tasks to specialized agents:
+
+```
+PR Review: #123 - Add user authentication
+═══════════════════════════════════════════════════
+
+Dispatching to review agents:
+├─ Security Reviewer     → analyzing...
+├─ Performance Analyst   → analyzing...
+├─ Maintainability Auditor → analyzing...
+└─ Test Validator        → analyzing...
+```
+
+### Step 3: Aggregate Findings
+
+Collect findings from all agents, each with:
+- Category (security, performance, maintainability, tests)
+- Severity (critical, major, minor, suggestion)
+- Confidence score (0.0 - 1.0)
+- File and line reference
+- Description
+- Suggested fix (if applicable)
+
+### Step 4: Filter by Confidence
+
+Only display findings with confidence >= 0.5:
+
+| Confidence | Label | Description |
+|------------|-------|-------------|
+| 0.9 - 1.0 | HIGH | Definite issue, must address |
+| 0.7 - 0.89 | MEDIUM | Likely issue, should address |
+| 0.5 - 0.69 | LOW | Possible concern, consider addressing |
+| < 0.5 | (suppressed) | Too uncertain to report |
+
+### Step 5: Generate Report
+
+```
+═══════════════════════════════════════════════════
+PR Review Report: #123
+═══════════════════════════════════════════════════
+
+Summary:
+  Files changed: 12
+  Lines added: 234
+  Lines removed: 45
+
+Findings: 8 total
+  🔴 Critical: 1
+  🟠 Major: 2
+  🟡 Minor: 3
+  💡 Suggestions: 2
+
+───────────────────────────────────────────────────
+CRITICAL FINDINGS
+───────────────────────────────────────────────────
+
+[SEC-001] SQL Injection Vulnerability (Confidence: 0.95)
+File: src/api/users.ts:45
+Category: Security
+
+The query uses string interpolation without parameterization:
+```ts
+const query = `SELECT * FROM users WHERE id = ${userId}`;
+```
+
+Suggested fix:
+```ts
+const query = 'SELECT * FROM users WHERE id = ?';
+db.query(query, [userId]);
+```
+
+───────────────────────────────────────────────────
+MAJOR FINDINGS
+───────────────────────────────────────────────────
+
+[PERF-001] N+1 Query Pattern (Confidence: 0.82)
+...
+
+───────────────────────────────────────────────────
+VERDICT
+───────────────────────────────────────────────────
+
+❌ REQUEST_CHANGES
+
+This PR has 1 critical security issue that must be addressed
+before merging. See SEC-001 above.
+
+───────────────────────────────────────────────────
+```
+
+### Step 6: Submit Review (Optional)
+
+```
+Submit this review to Gitea?
+1. Yes, with REQUEST_CHANGES
+2. Yes, as COMMENT only
+3. No, just show me the report
+```
+
+If yes, use `create_pr_review` MCP tool.
+
+## Output
+
+Full review report with:
+- Summary statistics
+- Findings grouped by severity
+- Code snippets with context
+- Suggested fixes
+- Overall verdict
+
+## Configuration
+
+| Variable | Default | Description |
+|----------|---------|-------------|
+| `PR_REVIEW_CONFIDENCE_THRESHOLD` | `0.5` | Minimum confidence to report |
+| `PR_REVIEW_AUTO_SUBMIT` | `false` | Auto-submit to Gitea |