feat: add ordered store migrations

docs/architecture.md

@@ -6,6 +6,12 @@ the shared Iroh endpoint, resource registry, module routing, and local control
 socket. Control commands connect to the Unix socket and send typed JSONL
 requests.
 
+The local metadata store is SQLite product state. `geth-store` tracks a numeric
+`schema_version` in the `meta` table and applies ordered migrations up to the
+crate's current schema version when the store opens. Fresh database creation and
+repeated opens are idempotent; migrations that change existing schemas run in a
+SQLite transaction where SQLite supports it.
+
 Service management is also exposed through the single binary. `geth daemon
 service ...` installs and controls a user-level service definition for the local
 daemon. The initial backends are systemd user units on Linux, launchd user agents

docs/production-readiness-roadmap.md

@@ -120,12 +120,12 @@ and downstream projects.
 Goal: treat local SQLite state as durable product data before users depend on
 it.
 
-- `[ ]` Replace opportunistic schema setup with ordered migrations.
+- `[x]` Replace opportunistic schema setup with ordered migrations.
   Acceptance criteria:
-  - `[ ]` The store tracks numeric schema versions.
-  - `[ ]` Each migration is transactional where SQLite supports it.
-  - `[ ]` Fresh database creation and repeated opens are idempotent.
-  - `[ ]` Old schema fixtures migrate to the current schema in tests.
+  - `[x]` The store tracks numeric schema versions.
+  - `[x]` Each migration is transactional where SQLite supports it.
+  - `[x]` Fresh database creation and repeated opens are idempotent.
+  - `[x]` Old schema fixtures migrate to the current schema in tests.
 
 - `[ ]` Make multi-table writes transactional.
   Acceptance criteria: