Add mol-bootstrap molecule for Gas Town installation

Defines a multi-step workflow for bootstrapping a new Gas Town installation:
- locate-harness: Interactive harness location selection
- create-harness: Directory structure creation
- setup-rigs: Rig configuration and cloning
- build-gt: Go binary compilation
- install-paths: PATH configuration
- init-beads: Beads database initialization
- sync-beads: Remote sync and doctor fixes
- verify: Installation verification

Note: Requires bd to support 'molecule' issue type (see gt-qn4l)

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

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

internal/beads/builtin_molecules.go

@@ -15,6 +15,7 @@ func BuiltinMolecules() []BuiltinMolecule {
 		QuickFixMolecule(),
 		ResearchMolecule(),
 		InstallGoBinaryMolecule(),
+		BootstrapGasTownMolecule(),
 	}
 }
 
@@ -123,6 +124,181 @@ gt --version  # if version command exists
 	}
 }
 
+// BootstrapGasTownMolecule returns the bootstrap molecule for new Gas Town installations.
+// This walks a user through setting up Gas Town from scratch after brew install.
+func BootstrapGasTownMolecule() BuiltinMolecule {
+	return BuiltinMolecule{
+		ID:    "mol-bootstrap",
+		Title: "Bootstrap Gas Town",
+		Description: `Complete setup of a new Gas Town installation.
+
+Run this after installing gt and bd via Homebrew. This molecule guides you through
+creating a harness, setting up rigs, and configuring your environment.
+
+## Step: locate-harness
+Determine where to install the Gas Town harness.
+
+Ask the user for their preferred location. Common choices:
+- ~/gt (recommended - short, easy to type)
+- ~/gastown
+- ~/workspace/gt
+
+Validate the path:
+- Must not already exist (or be empty)
+- Parent directory must be writable
+- Avoid paths with spaces
+
+Store the chosen path for subsequent steps.
+
+## Step: create-harness
+Create the harness directory structure.
+
+` + "```" + `bash
+mkdir -p {{harness_path}}
+cd {{harness_path}}
+gt install . --name {{harness_name}}
+` + "```" + `
+
+If the user wants to track the harness in git:
+` + "```" + `bash
+gt git-init --github={{github_repo}} --private
+` + "```" + `
+
+The harness now has:
+- mayor/ directory
+- .beads/ for town-level tracking
+- CLAUDE.md for mayor context
+
+Needs: locate-harness
+
+## Step: setup-rigs
+Configure which rigs to add to the harness.
+
+Default rigs for Gas Town development:
+- gastown (git@github.com:steveyegge/gastown.git)
+- beads (git@github.com:steveyegge/beads.git)
+
+For each rig, run:
+` + "```" + `bash
+gt rig add <name> <git-url> --prefix <prefix>
+` + "```" + `
+
+This creates the full rig structure:
+- refinery/rig/ (canonical main clone)
+- mayor/rig/ (mayor's working clone)
+- crew/main/ (default human workspace)
+- witness/ (polecat monitor)
+- polecats/ (worker directory)
+
+Needs: create-harness
+
+## Step: build-gt
+Build the gt binary from source.
+
+` + "```" + `bash
+cd {{harness_path}}/gastown/mayor/rig
+go build -o gt ./cmd/gt
+` + "```" + `
+
+Verify the build succeeded:
+` + "```" + `bash
+./gt version
+` + "```" + `
+
+Needs: setup-rigs
+Tier: haiku
+
+## Step: install-paths
+Install gt to a location in PATH.
+
+Check if ~/bin or ~/.local/bin is in PATH:
+` + "```" + `bash
+echo $PATH | tr ':' '\n' | grep -E '(~/bin|~/.local/bin|/home/.*/bin)'
+` + "```" + `
+
+Copy the binary:
+` + "```" + `bash
+mkdir -p ~/bin
+cp {{harness_path}}/gastown/mayor/rig/gt ~/bin/gt
+` + "```" + `
+
+If ~/bin is not in PATH, add to shell config:
+` + "```" + `bash
+echo 'export PATH="$HOME/bin:$PATH"' >> ~/.zshrc
+# or ~/.bashrc for bash users
+` + "```" + `
+
+Verify:
+` + "```" + `bash
+which gt
+gt version
+` + "```" + `
+
+Needs: build-gt
+Tier: haiku
+
+## Step: init-beads
+Initialize beads databases in all clones.
+
+For each rig's mayor clone:
+` + "```" + `bash
+cd {{harness_path}}/<rig>/mayor/rig
+bd init --prefix <rig-prefix>
+` + "```" + `
+
+For the town-level beads:
+` + "```" + `bash
+cd {{harness_path}}
+bd init --prefix gm
+` + "```" + `
+
+Configure sync-branch for multi-clone setups:
+` + "```" + `bash
+echo "sync-branch: beads-sync" >> .beads/config.yaml
+` + "```" + `
+
+Needs: setup-rigs
+Tier: haiku
+
+## Step: sync-beads
+Sync beads from remotes and fix any issues.
+
+For each initialized beads database:
+` + "```" + `bash
+bd sync
+bd doctor --fix
+` + "```" + `
+
+This imports existing issues from JSONL and sets up git hooks.
+
+Needs: init-beads
+Tier: haiku
+
+## Step: verify
+Verify the installation is complete and working.
+
+Run health checks:
+` + "```" + `bash
+gt status          # Should show rigs with crew/refinery/mayor
+gt doctor          # Check for issues
+bd list            # Should show issues from synced beads
+` + "```" + `
+
+Test spawning capability (dry run):
+` + "```" + `bash
+gt spawn --help
+` + "```" + `
+
+Print summary:
+- Harness location
+- Installed rigs
+- gt version
+- bd version
+
+Needs: sync-beads, install-paths`,
+	}
+}
+
 // SeedBuiltinMolecules creates all built-in molecules in the beads database.
 // It skips molecules that already exist (by title match).
 // Returns the number of molecules created.