Add Memos API adapter and settings UI

Introduce a Memos API adapter to unify compatibility across API flavors (v020-v021, v023, modern) and probe/detect server flavor. Add js/compat/memosApi.adapter.js and rename existing compat modules (memosApi.v024.js -> memosApi.modern.js, memosApi.v1.js -> memosApi.v020-v021.js) and trim probe from v023. Add settings UI support: new i18n keys in en/ja/ko/zh_CN, settings panel styles in css/main.css, new settings input binding and save flow in js (attachment-only default text persisted). Refactor oper.js to use the adapter for uploads, deletes, tag listing, search and image preview auth handling; add helper functions for attachment-only default text and settings payload. Update i18n bindings, popup, manifest and README changelog accordingly.
closed #5

css/main.css

@@ -170,6 +170,60 @@ a{color: #555;}
 }
 input.inputer{border-bottom: 1px solid #ccc;width:75%;}
 
+.settings-panel{
+    display: flex;
+    flex-direction: column;
+    gap: .75rem;
+    margin-top: .75rem;
+}
+
+.settings-section{
+    border: 1px solid rgb(229,231,235);
+    border-radius: .5rem;
+    background-color: rgb(255,255,255);
+    padding: .75rem;
+    display: flex;
+    flex-direction: column;
+    gap: .6rem;
+}
+
+.settings-section-title{
+    font-size: .9rem;
+    font-weight: 700;
+    color: rgb(55,65,81);
+}
+
+.settings-section-desc{
+    font-size: .75rem;
+    line-height: 1.35;
+    color: #7a7a7a;
+}
+
+.settings-input{
+    width: 100% !important;
+    box-sizing: border-box;
+    border: 1px solid rgb(229,231,235);
+    border-radius: .35rem;
+    background-color: #fafafa;
+    padding: .55rem .7rem;
+}
+
+.settings-input:focus{
+    border-color: rgb(22,163,74);
+    background-color: rgb(255,255,255);
+}
+
+.settings-textarea{
+    resize: vertical;
+    min-height: 4.5rem;
+    white-space: pre-wrap;
+}
+
+.settings-actions{
+    display: flex;
+    justify-content: flex-end;
+}
+
 #saveKey{margin:0;flex:1;}
 
 .common-tools-wrapper {