bazel: model storage, execution, search, knowledge, and API libraries

[DecisionNerd]

Context

Implements step 4 of #1: model storage, execution, search, knowledge, and API libraries as real Bazel targets.

Work

• Map remaining first-party library crates (storage, exec, search, knowledge, api, and peers named in the ledger) to Bazel labels.
• Preserve native link requirements and feature flags needed for correct builds.
• Update the migration ledger; keep drift check green.

Acceptance criteria

Given #10 foundation libraries build under Bazel
When storage, execution, search, knowledge, and API libraries are modeled
Then all 17 first-party packages (or current workspace count) have Bazel library coverage or an explicit retained-tool exception
And ordinary compilation/tests for these libs do not shell out to Cargo

Out of scope

• Full test/BDD/CLI/resource target graph (bazel: model unit, integration, snapshot, BDD, CLI, and resource targets #8).
• Binding cdylib packaging handoff (bazel: model PyO3 and napi-rs cdylibs plus packaging handoff #7).
• Mobile / UniFFI crates.

Evidence

• PR + ledger update; exact-head applicable CI green.
• Ordinary AGENTS.md close.

Relationships

• Parent / blocks: M2 gate: implement #1 Bazel migration via sub-agents #2
• Blocked by: bazel: model foundation and compiler-layer Rust libraries #10
• Blocks: bazel: model unit, integration, snapshot, BDD, CLI, and resource targets #8, bazel: model PyO3 and napi-rs cdylibs plus packaging handoff #7
• Canonical spec: build: migrate CI builds and tests to Bazel with Blacksmith caching #1 (Implementation Sequence step 4)