feat(plan-phase): ask user about research instead of silently deciding (#1075)

Instead of silently skipping research based on the config toggle,
plan-phase now asks the user whether to research before planning
(when no explicit --research or --skip-research flag is provided).

The prompt includes a contextual recommendation:
- 'Research first (Recommended)' for new features, integrations, etc.
- 'Skip research' for bug fixes, refactors, well-understood tasks

The --research and --skip-research flags still work as silent overrides
for automation. Auto mode (--auto) respects the config toggle silently.

Fixes #846

get-shit-done/workflows/plan-phase.md

@@ -174,12 +174,33 @@ If "Run discuss-phase first": Display `/gsd:discuss-phase {X}` and exit workflow
 
 ## 5. Handle Research
 
-**Skip if:** `--gaps` flag, `--skip-research` flag, or `research_enabled` is false (from init) without `--research` override.
+**Skip if:** `--gaps` flag or `--skip-research` flag.
 
 **If `has_research` is true (from init) AND no `--research` flag:** Use existing, skip to step 6.
 
 **If RESEARCH.md missing OR `--research` flag:**
 
+**If no explicit flag (`--research` or `--skip-research`) and not `--auto`:**
+Ask the user whether to research, with a contextual recommendation based on the phase:
+
+```
+AskUserQuestion([
+  {
+    question: "Research before planning Phase {X}: {phase_name}?",
+    header: "Research",
+    multiSelect: false,
+    options: [
+      { label: "Research first (Recommended)", description: "Investigate domain, patterns, and dependencies before planning. Best for new features, unfamiliar integrations, or architectural changes." },
+      { label: "Skip research", description: "Plan directly from context and requirements. Best for bug fixes, simple refactors, or well-understood tasks." }
+    ]
+  }
+])
+```
+
+If user selects "Skip research": skip to step 6.
+
+**If `--auto` and `research_enabled` is false:** Skip research silently (preserves automated behavior).
+
 Display banner:
 ```
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