PBI-56 + ST-1275: PLAN_READY → GRILLING re-grill + SKIPPED status rendering (#147)

* fix(ST-1272): allow PLAN_READY → GRILLING re-grill transition

actions/ideas.ts already lists PLAN_READY in GRILL_TRIGGERABLE_FROM,
but lib/idea-status.ts ALLOWED_TRANSITIONS was missing the
PLAN_READY → GRILLING edge. As a result, clicking Grill on a PLAN_READY
idea returned 422 "Status-transitie ongeldig" while the UI button was
enabled. Mirrors the existing PLANNED → GRILLING re-grill behaviour.

- lib/idea-status.ts: PLAN_READY allows GRILLING in addition to
  PLANNING/PLANNED
- __tests__/lib/idea-status.test.ts: explicit assert for
  PLAN_READY → GRILLING and PLAN_READY added to the regrill loop
  covering every GRILL_TRIGGERABLE_FROM status

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

* feat(ST-1275): render SKIPPED job status in chart-colors and insights

Closing the gap left when ClaudeJobStatus.SKIPPED was added to the schema:
the badge map and case-mapper already covered it, but the chart palette,
the per-day insights aggregator and the stacked-bar chart did not. SKIPPED
jobs (e.g. cmovkur8 manually flipped during the no-op-exit hotfix) now
render with a muted style consistent with cancelled.

- lib/chart-colors.ts: JOB_STATUS_COLORS gains a 'skipped' entry
  (var(--muted-foreground), same intensity as cancelled — neither rood/orange)
- lib/insights/agent-throughput.ts: DayCount + STATUSES + perDay zero-fill
  now include 'skipped'; the SQL terminal_7d filter already counted SKIPPED
- app/(app)/insights/components/agent-throughput.tsx: STACKED_STATUSES and
  the empty-state guard include 'skipped'
- __tests__: chart-colors keys list, job-status round-trip ('all 7 statuses')
  and the insights non-zero filter all account for SKIPPED

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

lib/insights/agent-throughput.ts

@@ -8,6 +8,7 @@ export interface DayCount {
   done: number
   failed: number
   cancelled: number
+  skipped: number
 }
 
 export interface ThroughputKpi {
@@ -21,6 +22,8 @@ export interface JobsPerDayResult {
   kpi: ThroughputKpi
 }
 
+const STATUSES = ['queued', 'claimed', 'running', 'done', 'failed', 'cancelled', 'skipped'] as const
+
 type RawDayRow = { day: Date; status: string; count: bigint }
 type RawKpiRow = { today_count: bigint; done_7d: bigint; terminal_7d: bigint; avg_seconds: number | null }
 
@@ -98,6 +101,7 @@ export async function getJobsPerDay(
       done: statusMap.get('done') ?? 0,
       failed: statusMap.get('failed') ?? 0,
       cancelled: statusMap.get('cancelled') ?? 0,
+      skipped: statusMap.get('skipped') ?? 0,
     })
   }