chore: bootstrap repo with chunks 1 and 2

Establishes the global AI development config repo from scratch:

- Chunk 1: repo skeleton, install.sh, statusline, deploy manifest
- Chunk 2: core instructions (coding/git/testing), CLAUDE.md rewrite
  (always-on + content index two-tier model), docs restructure,
  6 ADRs, ROADMAP.md, .gitkeep placeholders
- Bootstrap skills in .claude/skills/ (to be catalogued and migrated
  to .agents/skills/ in Chunk 3)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

docs/issues/0006-git-instructions.md

@@ -0,0 +1,19 @@
+# 0006 — Write core/instructions/git.md ✅
+
+## What to build
+
+Create the git conventions instruction file at `core/instructions/git.md`. Plain markdown, no frontmatter. The agent reads this file on demand when doing git operations, as directed by the content index in `providers/claude-code/CLAUDE.md`.
+
+The file establishes five key rules: never skip hooks (`--no-verify`); never force-push main or master; commit messages explain why, not what; never commit secrets or credentials; and the conventional commits vocabulary (`feat:`, `fix:`, `docs:`, `chore:`, `refactor:`, `test:`).
+
+## Acceptance criteria
+
+- [ ] File exists at `core/instructions/git.md`
+- [ ] Contains all five rules from the PRD Module 3 section, including the conventional commits vocabulary
+- [ ] Plain markdown with no frontmatter or schema
+- [ ] In a new session, ask the agent to commit a change — agent uses conventional commits format unprompted
+- [ ] In a new session, ask the agent to skip a pre-commit hook — agent refuses
+
+## Blocked by
+
+- 0004 — rewrite providers/claude-code/CLAUDE.md and retire global.md