feat: add /catch-up and /debug guided commands to draft welcome

Replace the 'What changed recently' draft chip with /catch-up, a command
whose hidden prompt branches on git state: reconstruct intent from an
in-progress diff, check an open PR's review state, or summarize recent
commits.

Add /debug as a new draft chip and command: a guided root-cause
investigation that captures the symptom, forms hypotheses, checks them
against the code, and confirms the cause before proposing a fix.

Both follow the /workspace-review pattern — visible + hidden magic
prompts wired into command autocomplete, the submit handler, draft preset
chips, and the Magic Prompts settings page, with i18n across all locales.

packages/ui/src/lib/i18n/messages/en.settings.ts

@@ -224,6 +224,8 @@ export const settingsDict = {
   'settings.magicPrompts.sidebar.item.sessionSummary': 'Session Summary',
   'settings.magicPrompts.sidebar.item.sessionWorkspaceReview': 'Workspace Review',
   'settings.magicPrompts.sidebar.item.sessionFeaturePlan': 'Feature Planning',
+  'settings.magicPrompts.sidebar.item.sessionCatchUp': 'Catch Up',
+  'settings.magicPrompts.sidebar.item.sessionDebug': 'Debugging',
   'settings.magicPrompts.sidebar.item.sessionFusion': 'Fusion',
   'settings.remoteInstances.sidebar.title': 'Remote Instances',
   'settings.remoteInstances.sidebar.total': 'Total {count}',
@@ -1689,6 +1691,10 @@ export const settingsDict = {
   'settings.magicPrompts.page.group.sessionWorkspaceReview.description': 'Prompts used by the /workspace-review slash command: visible user message + hidden instructions. Reviews current workspace changes for high-signal issues only.',
   'settings.magicPrompts.page.group.sessionFeaturePlan.title': 'Feature Planning',
   'settings.magicPrompts.page.group.sessionFeaturePlan.description': 'Prompts used by the /plan-feature slash command: visible user message + hidden instructions. Runs a guided dialogue that researches the code and asks clarifying questions in small batches before producing an implementation plan.',
+  'settings.magicPrompts.page.group.sessionCatchUp.title': 'Catch Up',
+  'settings.magicPrompts.page.group.sessionCatchUp.description': 'Prompts used by the /catch-up slash command: visible user message + hidden instructions. Inspects git state and branches on it — reconstructs intent from an in-progress diff, checks an open PR\'s review state, or summarizes recent commits.',
+  'settings.magicPrompts.page.group.sessionDebug.title': 'Debugging',
+  'settings.magicPrompts.page.group.sessionDebug.description': 'Prompts used by the /debug slash command: visible user message + hidden instructions. Runs a guided root-cause investigation — captures the symptom, forms hypotheses, checks them against the code, and confirms the cause before proposing a fix.',
   'settings.magicPrompts.page.group.sessionFusion.title': 'Fusion',
   'settings.magicPrompts.page.group.sessionFusion.description': 'Prompts used when combining multi-run outputs into one final answer: visible user message + hidden instructions before source results.',
   'settings.magicPrompts.page.actions.resetting': 'Resetting...',