feat(close): Add --suggest-next flag to show newly unblocked issues (GH#679)

When closing an issue, the new --suggest-next flag returns a list of
issues that became unblocked (ready to work on) as a result of the close.

This helps agents and users quickly identify what work is now available
after completing a blocker.

Example:
  $ bd close bd-5 --suggest-next
  ✓ Closed bd-5: Completed

  Newly unblocked:
    • bd-7 "Implement feature X" (P1)
    • bd-8 "Write tests for X" (P2)

Implementation:
- Added GetNewlyUnblockedByClose to storage interface
- Implemented efficient single-query for SQLite using blocked_issues_cache
- Added SuggestNext field to CloseArgs in RPC protocol
- Added CloseResult type for structured response
- CLI handles both daemon and direct modes

Thanks to @kraitsura for the detailed feature request and design.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

docs/MOLECULES.md

@@ -238,49 +238,18 @@ bd wisp gc             # Garbage collect old wisps
 For reference, here's how the layers stack:
 
 ```
-Formulas (.formula.json)                  ← SOURCE: shareable workflow definitions
-    ↓ cook (ephemeral)
-[Protos]                                  ← TRANSIENT: compiled templates (auto-deleted)
-    ↓ pour/wisp
-Molecules (bond, squash, burn)            ← EXECUTION: workflow operations
+Formulas (JSON compile-time macros)      ← optional, for complex composition
+    ↓
+Protos (template issues)                  ← optional, for reusable patterns
+    ↓
+Molecules (bond, squash, burn)            ← workflow operations
     ↓
 Epics (parent-child, dependencies)        ← DATA PLANE (the core)
     ↓
 Issues (JSONL, git-backed)                ← STORAGE
 ```
 
-**Protos are ephemeral**: When you `bd pour formula-name` or `bd wisp create formula-name`, the formula is cooked into a temporary proto, used to spawn the mol/wisp, then automatically deleted. Protos are an implementation detail, not something users manage directly.
-
-**Most users only need the bottom two layers.** Formulas are for sharing reusable patterns.
-
-## Distillation: Extracting Patterns
-
-The lifecycle is circular - you can extract formulas from completed work:
-
-```
-Formulas ──cook──→ Mols/Wisps ──distill──→ Formulas
-```
-
-**Use cases for distillation:**
-- **Emergent patterns**: Manually structured an epic that worked well
-- **Modified execution**: Poured a formula but added custom steps
-- **Learning from success**: Extract what made a complex mol succeed
-
-```bash
-bd distill <mol-id> -o my-workflow.formula.json   # Extract formula from mol
-```
-
-## Sharing: The Mol Mall
-
-All workflow sharing happens via formulas:
-
-```bash
-bd mol publish my-workflow.formula.json            # Share to GitHub repo
-bd mol install github.com/org/mol-code-review      # Install from GitHub
-bd pour mol-code-review --var repo=myproject       # Use installed formula
-```
-
-Formulas are clean source code: composable, versioned, parameterized. Mols contain execution-specific context and aren't shared directly.
+**Most users only need the bottom two layers.** Protos and formulas are for reusable patterns and complex composition.
 
 ## Commands Quick Reference