Re-home this session's new ADRs (0039-0049) and issues (032-037) onto the consolidated scheme; flip issue 003; port repos.md sdk line + feature-branches playbook (07); regenerate index

Claude-Session: https://claude.ai/code/session_01LrgweAeERJYBg88c5cKDzF

00-META/process/00-overview.md

@@ -50,6 +50,7 @@ the expensive half.
 | [04](04-build-handoff.md) | Build handoff | A design is ready to be built |
 | [05](05-constitution-sync.md) | Constitution sync | `how-we-build.md` changed a rule the mesh enforces |
 | [06](06-writing-a-module.md) | Writing a module | Something that runs today must run on the mesh |
+| [07](07-feature-branches.md) | Feature branches across repos | Work that changes code, in one repo or several at once |
 
 ## Status lives in frontmatter
 

00-META/process/07-feature-branches.md

@@ -0,0 +1,57 @@
+# Playbook 07 — Feature branches across repos
+
+**Trigger.** Work that changes code — in one code repo or in several at once (`mesh-sdk`,
+`mesh-control`, `mesh-catalog`, `mesh-host`, `mesh-lab`, and `hq` when a decision rides along).
+
+**Who runs it.** Anyone who writes code, engineers and agents alike. Agents follow it exactly —
+it is the guard against the failure it was written for.
+
+## The failure it prevents
+
+A feature was worked as a branch-and-MR per *unit of thought* — one per decision, one per
+stacked increment — and each MR was treated as finished when it was *opened*, not when it was
+*merged*. Across repos the same feature took a different branch name in each. The MRs piled up
+unmerged: one session left **sixteen** stacked intermediate MRs that had to be consolidated and
+closed by hand. An MR is a review checkpoint, not a scratchpad.
+
+## The rule
+
+One feature is **one branch name**, **one worktree per repo**, **one MR per repo**, opened
+**once, at the end**.
+
+1. **Name the feature once.** `feat/<slug>`. The *same* branch name in every repo the feature
+   touches — never a different name per repo, never a fresh branch per increment within the
+   feature.
+2. **Isolate each repo.** One git worktree per touched repo under `.work/<slug>/<repo>`, branched
+   off `main`:
+   ```
+   git worktree add .work/<slug>/<repo> -b feat/<slug> origin/main
+   ```
+   Parallel features never collide, and no shared checkout is edited.
+3. **Commit as you go — locally.** Increments land on the one branch. Nothing is pushed and no
+   MR is opened mid-feature.
+4. **Finish, then publish.** When the whole feature is done — every repo, tests green — push
+   every branch and open **one MR per touched repo**, together.
+5. **Merge promptly, once approved.** Every merge into `main` is notified and approved
+   ([ADR 0023](../../02-DECISIONS/0023-approval-is-the-checkpoint.md)); once it is, merge —
+   do not leave it sitting. The branch is deleted on merge.
+6. **Leave nothing behind.** After the MRs merge, no `feat/<slug>` branch and no `.work/<slug>`
+   worktree survive.
+
+## What this is not
+
+- **Not a licence to batch unbounded work.** A feature is a *bounded* unit; if it sprawls for
+  days, end-of-feature bloat merely replaces per-increment bloat. Split it into features, each
+  its own branch and MR.
+- **Not a second trunk.** Every repo branches off `main`. There is no longer an `initialization`
+  trunk.
+
+## How it is checked
+
+The end state is visible, and its absence is the smell:
+
+- After a feature merges, `git branch -r | grep feat/<slug>` and `git worktree list` return
+  nothing for it. A surviving branch or worktree means step 6 was skipped.
+- More than one open MR in a repo that share no feature name, or a stack of MRs none of which is
+  merged, is the failure this playbook exists to prevent — stop and consolidate before opening
+  more.

00-META/repos.md

@@ -31,7 +31,7 @@ target, not the present.
 | `mesh-substrate` | 1 | the four pinned services, as declarations |
 | `mesh-control` | 2 | **exists.** The control plane and its contexts — one of seven built ([ADR 0006](../02-DECISIONS/0006-the-substrate-and-the-control-plane.md)) |
 | `mesh-surfaces` | 3 | tools, web, cli |
-| `mesh-sdk` | — | contracts shared across tiers |
+| `mesh-sdk` | — | the stable spine modules build against — the tool-serving harness, the messaging/event framework, the contracts and core primitives. Holds nothing per-module and nothing volatile ([ADR 0039](../02-DECISIONS/0039-what-the-sdk-holds-and-refuses.md)). |
 | `mesh-lab` | — | **exists.** The lab — scenario lifecycle, networking, placement. Ships to nobody; runs on a workstation. |
 
 Tier 4's shape is open, and deliberately so: see ADR 0019 and