feat(fusion_clock): open shifts + self-assign + bulk apply [B4-B5]

Model: fclk_create_open_shifts/claim_open_shift/release_shift (days-before
cutoff + role eligibility)/bulk_apply. Planner: Open Shift… panel, open-shifts
strip with delete, Apply-to-dept; load includes open shifts. Portal: claim
open shifts + release own upcoming shifts with feedback banners. Tests for
claim/role-gate/release/bulk.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

fusion_clock/static/src/css/portal_schedule.css

@@ -103,6 +103,53 @@
     font-style: italic;
 }
 
+/* ---- Claim / release feedback + open shifts ---- */
+.fpl-flash {
+    margin: 0 16px 12px;
+    padding: 10px 14px;
+    border-radius: 8px;
+    font-size: 13px;
+}
+
+.fpl-flash-err {
+    background: rgba(239, 68, 68, 0.10);
+    border: 1px solid rgba(239, 68, 68, 0.30);
+    color: #ef4444;
+}
+
+.fpl-flash-ok {
+    background: rgba(16, 185, 129, 0.10);
+    border: 1px solid rgba(16, 185, 129, 0.25);
+    color: var(--fclk-green);
+}
+
+.fpl-open-item {
+    align-items: center;
+    justify-content: space-between;
+}
+
+.fpl-claim-form,
+.fpl-release-form {
+    display: inline-block;
+    margin: 0;
+}
+
+.fpl-release-btn {
+    display: block;
+    margin-top: 4px;
+    background: transparent;
+    border: 1px solid rgba(239, 68, 68, 0.35);
+    color: #ef4444;
+    font-size: 11px;
+    border-radius: 6px;
+    padding: 2px 8px;
+    cursor: pointer;
+}
+
+.fpl-release-btn:hover {
+    background: rgba(239, 68, 68, 0.10);
+}
+
 /* ---- Bottom padding so nav doesn't cover last shift ---- */
 .fclk-container {
     padding-bottom: 80px;