Release exp batch: narrow-screen CSS fixes — approval/clarify popup min-width (#6104) + stream-timestamp foldable layout (#6106).

Scoped to the two stated fixes only: strips the #composerModelDropdown position:fixed
mobile override that #6104's branch had bundled in (that's the #6080 model-picker
mechanism, being reworked separately to reparent to body level — the fixed override
is trapped by .composer-footer's container-type so it doesn't belong here), and drops
the <=360px tool-name-hiding rules (header overflow-clip prevents the spill without
losing tool identity). Thanks @webtecnica.

CHANGELOG.md

@@ -71,6 +71,10 @@
 
 ### Fixed
 
+- **Approval and clarify popups no longer collapse to tiny blank windows on very narrow screens.** On very narrow viewports the clarify card could shrink to an unreadable sliver; it now gets a `min-width` and `overflow:visible` matching the approval card. Thanks @webtecnica. (#6104, #6094)
+
+- **Stream event timestamps no longer break the row layout on narrow foldable screens.** On screens under 360px the per-event timestamps could spill out of tool/thinking card headers; the headers now clip overflow so the timestamp layout holds. (Tool names stay visible — an earlier draft hid them at ≤360px, which lost tool identity; the header clip alone prevents the spill.) Thanks @webtecnica. (#6106, #6099)
+
 - **Streaming sidebar polls no longer re-run the expensive CLI/cron projection every few seconds.** The per-stream cache TTL was pinned at 30s while the frontend's streaming sidebar poll cadence could approach it, so the state.db CLI/cron projection (and its ~200 sidecar reads) could be re-paid on nearly every poll during a live turn (the #4842/#4808 high-CPU `get_cli_sessions` case). The streaming TTL is now held strictly above the sidebar poll interval (45s) and paired with the stable streaming cache key, so repeated polls reuse the projection; a new test asserts the TTL stays above the poll cadence so this can't silently regress. Thanks @starship-s. (#6102, #4842)
 
 - **Delegated subagent sessions in the sidebar now show a meaningful title instead of "Subagent Session".** Generic delegated child sessions previously all displayed the placeholder "Subagent Session" in the conversations list, making them indistinguishable. Their sidebar title is now derived (view-only) from the child's first user message during the existing batched sidebar-metadata pass — without mutating the stored session title, so the read-only boundary is preserved. Only generic "Subagent Session" placeholders are affected; custom titles are left untouched. Thanks @rodboev. (#6056, #6033)

static/style.css

@@ -3117,8 +3117,6 @@
     .composer-mobile-config-panel.open{display:flex;}
     .composer-mobile-config-action{box-sizing:border-box;flex:1 1 0;min-height:44px;min-width:0;background:var(--input-bg);border-color:var(--border);}
     .composer-mobile-context-action{flex:1 0 100%;}
-    /* Keep the rich picker in the visual viewport when mobile browser chrome moves. */
-    #composerModelDropdown{position:fixed;bottom:auto;box-sizing:border-box;min-width:0;width:calc(100vw - 16px);max-width:calc(100vw - 16px);z-index:220;}
     /* icon-only composer chips continue below mobile widths */
     .composer-divider{display:none;}
     .composer-status{flex:0 1 auto;min-width:0;max-width:96px;font-size:10px;text-align:right;}
@@ -3248,10 +3246,6 @@
 .ws-dropdown.open{display:block;}
 .ws-dropdown-footer{left:0;right:auto;bottom:calc(100% + 4px);min-width:280px;max-width:min(420px,calc(100vw - 32px));}
 .model-dropdown{display:none;position:absolute;bottom:calc(100% + 4px);left:0;min-width:280px;max-width:min(420px,calc(100vw - 32px));background:var(--surface);border:1px solid var(--border2);border-radius:10px;box-shadow:0 -4px 24px rgba(0,0,0,.4);z-index:200;overflow:hidden;max-height:min(70vh,640px);overflow-y:auto;}
-/* Re-assert the mobile picker after the base dropdown rule below the phone media block. */
-@media (max-width:640px){
-  #composerModelDropdown{position:fixed;bottom:auto;box-sizing:border-box;min-width:0;width:calc(100vw - 16px);max-width:calc(100vw - 16px);z-index:220;}
-}
 .model-dropdown.open{display:block;}
 .model-scope-note{position:sticky;top:0;z-index:2;padding:9px 14px;border-bottom:1px solid var(--border);color:var(--text);font-size:11px;font-weight:650;line-height:1.4;background:color-mix(in srgb,var(--surface) 82%,var(--accent-bg));box-shadow:0 1px 0 rgba(0,0,0,.12);}
 .model-group{padding:8px 14px 4px;font-size:10px;font-weight:700;letter-spacing:.04em;color:var(--muted);text-transform:uppercase;border-top:1px solid var(--border2);margin-top:2px;}.model-group.collapsible{cursor:pointer;user-select:none}.model-group.collapsible:before{content:'\25b6';display:inline-block;font-size:8px;margin-right:5px;transition:transform .15s ease}.model-group.collapsible.open:before{transform:rotate(90deg)}.model-group-body:empty{display:none}
@@ -4126,9 +4120,6 @@ body.resizing .sidebar{transition:none!important;}
   text-overflow:ellipsis;
   white-space:nowrap;
 }
-@media (max-width:360px){
-  .transparent-event-row .tool-card-name{display:none;}
-}
 .transparent-event-row .tool-card-title,
 .transparent-event-row .tool-card-preview{
   display:inline;
@@ -4158,13 +4149,6 @@ body.resizing .sidebar{transition:none!important;}
 @media (max-width:420px){
   .transparent-event-time{ display:none; }
 }
-/* Very narrow foldables (~280-360px): hide the tool name label so the
-   preview (the most informative part) doesn't get squeezed to zero.
-   The icon + preview + status is enough to identify the event, and
-   the full name is visible on expand/hover. (#6099) */
-@media (max-width:360px){
-  .transparent-event-row .tool-card-name{ display:none; }
-}
 .transparent-event-row .thinking-card-label{
   display:inline;
   flex:0 0 auto;