fix(ui): cookie-authed users' writes silently stranded behind bearer gates

THE CLASS: the /api JWT middleware's TokenLookup is
"cookie:token,header:Authorization:Bearer" — the token cookie always
rides same-origin fetches, so a signed-in user never needs the
localStorage bearer. But a dozen call sites gated their fetch on
`localStorage.getItem("token")` and early-returned when absent. The
global 401 interceptor CLEARS that localStorage entry on any session
rotation/blip — after which every gated write silently did nothing:
theme changes reverted on reload (the reported "can no longer change
themes", on top of the interpolation bug d5dbaa48 fixed), chain-order
selects, collection deletion, Add-to-collection submits, filter
save/load/delete, conflict actions, linking actions, stats charts,
tag suggestions, device management, admin scanner actions — all dead
for perfectly authenticated cookie users.

Fix: storage.ts exports authHeaders() (bearer when present, cookie
carries otherwise) and every gate/header site now uses it — theme.ts,
collections.ts (htmx auth, doRemoveBook/doBulkRemove, setChainOrder),
bookPicker submit, filter_builder suggestions + match count,
collection-rules apply hook, bookshelf save/load/delete filter,
conflicts x4, linking x3, admin scanner actions + polls (requireToken
removed — its "Session expired" toast fired for cookie users too),
dashboard preferences/sections, custom-section-builder, header
scanner poll, stats x3, tag suggestions, profile delete-account
(which also wrongly redirected cookie users to /login), and
device-management x4. Reads keep their graceful-empty behavior; the
bearers still ride along when present.

Pinned: the knob-matrix theme spec now REMOVES localStorage.token and
asserts the theme PUT still fires (cookie-only) and the class flips —
the exact strand that started this.

Found by noticing the panel browser's Nord click switched the class
but produced no PUT: the persistence half was gated on a token the
401 interceptor had cleared.

web/src/conflicts.ts

@@ -1,4 +1,5 @@
 import { Alpine } from "./alpine";
+import { authHeaders } from "./storage";
 import { showToast } from "./toast";
 
 async function refreshConflicts(): Promise<void> {
@@ -85,14 +86,12 @@ async function resolveConflict(
   winner: string,
   manualData?: Record<string, unknown>,
 ): Promise<void> {
-  const token = localStorage.getItem("token");
-  if (!token) return;
+  // cookie auth carries the call; a null bearer must not strand it
 
   try {
     const response = await fetch(`/api/conflicts/${conflictId}/resolve`, {
       method: "POST",
       headers: {
-        Authorization: `Bearer ${token}`,
         "Content-Type": "application/json",
       },
       body: JSON.stringify({ winner, manual_data: manualData }),
@@ -115,14 +114,12 @@ async function bulkResolve(
   strategy: "most_recent" | "highest_progress",
   conflictIds: string[],
 ): Promise<void> {
-  const token = localStorage.getItem("token");
-  if (!token) return;
+  // cookie auth carries the call; a null bearer must not strand it
 
   try {
     const response = await fetch("/api/conflicts/bulk-resolve", {
       method: "POST",
       headers: {
-        Authorization: `Bearer ${token}`,
         "Content-Type": "application/json",
       },
       body: JSON.stringify({ conflict_ids: conflictIds, strategy }),
@@ -140,14 +137,12 @@ async function bulkResolve(
 }
 
 async function bulkDismiss(conflictIds: string[]): Promise<void> {
-  const token = localStorage.getItem("token");
-  if (!token) return;
+  // cookie auth carries the call; a null bearer must not strand it
 
   try {
     const response = await fetch("/api/conflicts/bulk-dismiss", {
       method: "POST",
       headers: {
-        Authorization: `Bearer ${token}`,
         "Content-Type": "application/json",
       },
       body: JSON.stringify({ conflict_ids: conflictIds }),
@@ -164,13 +159,12 @@ async function bulkDismiss(conflictIds: string[]): Promise<void> {
 }
 
 async function dismissAllResolved(): Promise<void> {
-  const token = localStorage.getItem("token");
-  if (!token) return;
+  // cookie auth carries the call; a null bearer must not strand it
 
   try {
     const response = await fetch("/api/conflicts/dismiss-resolved", {
       method: "POST",
-      headers: { Authorization: `Bearer ${token}` },
+      headers: authHeaders(),
     });
 
     if (response.ok) {