feat(edda-ledger): add error context enrichment across ledger, serve, and CLI

[fagemx]

Summary

Closes #377

• Layer 1 (edda-ledger ledger.rs): Added .context() / .with_context() to all 45+ Ledger public methods that delegate to SqliteStore. Each context string includes the method name and key identifying parameters (e.g., Ledger::active_decisions(domain=Some("db"))). This enriches errors for ALL callers (serve, CLI, MCP, bridge).

• Layer 2 (edda-serve lib.rs): Added .context() to all 33 handler open_ledger() calls with the HTTP route name (e.g., GET /api/decisions). This creates a two-layer error chain: GET /api/decisions > Ledger::active_decisions > sqlite error.

• Layer 3 (CLI): Added .context() to Ledger::open() calls in cmd_draft.rs (8 functions), cmd_bridge.rs (2 functions), and cmd_pair.rs (4 functions) with command name context.

Changes

File	Changes
crates/edda-ledger/src/ledger.rs	use anyhow::Context + .context() on 45+ delegation methods
crates/edda-serve/src/lib.rs	use anyhow::Context + .context() on 33 handler open_ledger() calls
crates/edda-cli/src/cmd_draft.rs	.context() on 8 Ledger::open() calls
crates/edda-cli/src/cmd_bridge.rs	use anyhow::Context + .context() on 2 Ledger::open() calls
crates/edda-cli/src/cmd_pair.rs	use anyhow::Context + .context() on 4 Ledger::open() calls

Test plan

• cargo fmt --check passes
• cargo clippy -p edda-ledger -p edda-serve -p edda -- -D warnings passes with zero warnings
• cargo test --workspace passes (all 1400+ tests, 0 failures)
• No behavioral changes -- only error message strings are enriched
• No API changes -- all return types remain anyhow::Result<T>

🤖 Generated with Claude Code

[fagemx]

Code Review: PR #381 (Round 1) — LGTM 🎉

All P0 and P1 issues have been resolved.

Summary

This PR adds systematic anyhow::Context enrichment across three layers of the error chain:

• Layer 1 (edda-ledger ledger.rs): 45+ Ledger public methods now carry method-name context with key parameters (e.g., Ledger::get_event(evt_xxx)). Uses .context() for parameterless methods and .with_context(|| format!(...)) for parameterized ones — consistent throughout.
• Layer 2 (edda-serve lib.rs): All 33 handler open_ledger() calls tagged with METHOD /api/route context strings, plus 1 Ledger::open() call in post_approval_check.
• Layer 3 (CLI): cmd_draft.rs (8), cmd_bridge.rs (2), cmd_pair.rs (4) — all Ledger::open() calls enriched with module::function: opening ledger pattern.

Quality Checks

Check	Result
cargo fmt --check	✅ Clean
cargo clippy --workspace -- -D warnings	✅ Zero warnings
cargo test --workspace	✅ All 1400+ tests pass
Context string consistency	✅ Layer-appropriate patterns used consistently
No behavioral changes	✅ Only error message enrichment
No new dependencies	✅ anyhow already a workspace dep

Verdict: LGTM ✅

No critical or high-priority issues remaining. This PR is ready for merge.

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Completed after 1 round(s) of automated review-fix loop