chore: initial backup of Claude Code configuration

Includes: CLAUDE.md, settings.json, agents, commands, rules, skills,
hooks, contexts, evals, get-shit-done, plugin configs (installed list
and marketplace sources). Excludes credentials, runtime caches,
telemetry, session data, and plugin binary cache.

commands/gsd/validate-phase.md

@@ -0,0 +1,35 @@
+---
+name: gsd:validate-phase
+description: Retroactively audit and fill Nyquist validation gaps for a completed phase
+argument-hint: "[phase number]"
+allowed-tools:
+  - Read
+  - Write
+  - Edit
+  - Bash
+  - Glob
+  - Grep
+  - Task
+  - AskUserQuestion
+---
+<objective>
+Audit Nyquist validation coverage for a completed phase. Three states:
+- (A) VALIDATION.md exists — audit and fill gaps
+- (B) No VALIDATION.md, SUMMARY.md exists — reconstruct from artifacts
+- (C) Phase not executed — exit with guidance
+
+Output: updated VALIDATION.md + generated test files.
+</objective>
+
+<execution_context>
+@C:/Users/yaoji/.claude/get-shit-done/workflows/validate-phase.md
+</execution_context>
+
+<context>
+Phase: $ARGUMENTS — optional, defaults to last completed phase.
+</context>
+
+<process>
+Execute @C:/Users/yaoji/.claude/get-shit-done/workflows/validate-phase.md.
+Preserve all workflow gates.
+</process>