Simplify the project view header: drop the back link and description

- Remove the '<- All projects' link at the top -- the sidebar's
  Dashboard link already covers that.
- Remove the description textarea and all of its state/save logic
  (descriptionDraft, saveDescription, patchProject's description
  field); the backend field and API are untouched.
- Drop .project__chrome's 42rem max-width, which existed only to keep
  the now-gone description prose readable. The header (title + Manage
  menu) now spans the full wide-layout width, so Manage sits at the
  true top right instead of a narrower centred column.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

web/src/style.css

@@ -473,7 +473,7 @@ h1 {
   background: var(--bg);
 }
 
-/* --- project detail: header, inline title/description, manage menu - */
+/* --- project detail: header, inline title, manage menu ----------------- */
 
 .project-head {
   display: flex;
@@ -487,10 +487,11 @@ h1 {
   margin: 0 0 0.5rem;
 }
 
-.project-head__title input,
-.project-head__desc {
+.project-head__title input {
   width: 100%;
   font: inherit;
+  font-size: 1.4rem;
+  font-weight: 600;
   color: var(--text);
   background: transparent;
   border: 1px solid transparent;
@@ -498,31 +499,13 @@ h1 {
   padding: 0.25rem 0.4rem;
 }
 
-.project-head__title input {
-  font-size: 1.4rem;
-  font-weight: 600;
-}
-
-.project-head__desc {
-  display: block;
-  resize: vertical;
-  min-height: 2.75rem;
-  font-size: 0.95rem;
-  color: var(--muted);
-  margin-bottom: 0.75rem;
-}
-
-.project-head__title input:hover,
-.project-head__desc:hover {
+.project-head__title input:hover {
   border-color: var(--border);
 }
 
-.project-head__title input:focus,
-.project-head__desc:focus {
-  outline: none;
+.project-head__title input:focus {
   color: var(--text);
   background: var(--bg);
-  border-color: var(--accent);
 }
 
 .menu {
@@ -587,12 +570,6 @@ h1 {
   color: var(--error);
 }
 
-/* --- project detail: keep the header/prose readable on the wide layout -- */
-
-.project__chrome {
-  max-width: 42rem;
-}
-
 /* --- tabs -------------------------------------------------------------- */
 
 .tabs {