feat: basecamp-project skill

.pi/gsd/references/decimal-phase-calculation.md

@@ -0,0 +1,64 @@
+# Decimal Phase Calculation
+
+Calculate the next decimal phase number for urgent insertions.
+
+## Using gsd-tools
+
+```bash
+# Get next decimal phase after phase 6
+node ".pi/gsd/bin/gsd-tools.cjs" phase next-decimal 6
+```
+
+Output:
+```json
+{
+  "found": true,
+  "base_phase": "06",
+  "next": "06.1",
+  "existing": []
+}
+```
+
+With existing decimals:
+```json
+{
+  "found": true,
+  "base_phase": "06",
+  "next": "06.3",
+  "existing": ["06.1", "06.2"]
+}
+```
+
+## Extract Values
+
+```bash
+DECIMAL_PHASE=$(node ".pi/gsd/bin/gsd-tools.cjs" phase next-decimal "${AFTER_PHASE}" --pick next)
+BASE_PHASE=$(node ".pi/gsd/bin/gsd-tools.cjs" phase next-decimal "${AFTER_PHASE}" --pick base_phase)
+```
+
+Or with --raw flag:
+```bash
+DECIMAL_PHASE=$(node ".pi/gsd/bin/gsd-tools.cjs" phase next-decimal "${AFTER_PHASE}" --raw)
+# Returns just: 06.1
+```
+
+## Examples
+
+| Existing Phases | Next Phase |
+|-----------------|------------|
+| 06 only | 06.1 |
+| 06, 06.1 | 06.2 |
+| 06, 06.1, 06.2 | 06.3 |
+| 06, 06.1, 06.3 (gap) | 06.4 |
+
+## Directory Naming
+
+Decimal phase directories use the full decimal number:
+
+```bash
+SLUG=$(node ".pi/gsd/bin/gsd-tools.cjs" generate-slug "$DESCRIPTION" --raw)
+PHASE_DIR=".planning/phases/${DECIMAL_PHASE}-${SLUG}"
+mkdir -p "$PHASE_DIR"
+```
+
+Example: `.planning/phases/06.1-fix-critical-auth-bug/`