feat(web): inline-expand summary + Q&A in the list (ADR-031, #16)

Click a summarized card → its full summary (summaryBody) + chat dock (chatReveal)
expand in place via HTMX (GET /v/{id}/expand → expandedCard), collapse back via
GET /v/{id}/card → compact VideoCard. Same <li id>, outerHTML swap — the existing
list-fragment pattern. The card title carries href=/v/{id} as the no-JS fallback
(detail page stays for no-JS + deep links); only summarized cards expand. Reuses
summaryBody + chatReveal so the expanded card never drifts from the detail page.

BDD: inline_expand.feature un-pended + mapped. TDD: 6 handler/fragment tests
(expand/collapse fragments, chat dock, summarized-only, no-JS href, shared body).
Minimal CSS only — the TUI/charm restyle is #17.

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

internal/web/views.templ

@@ -264,7 +264,16 @@ templ summaryList(b listBuckets, hasConnected bool, autoSummarize bool) {
 templ VideoCard(r store.SummaryRow) {
 	<li class={ "card", templ.KV("card-pending", !r.Summarized) } id={ "video-" + r.VideoID }>
 		if r.Summarized {
-			<div class="card-title"><a href={ videoURL(r.VideoID) }>{ displayTitle(r) }</a></div>
+			// Expand the full summary + Q&A in place (ADR-031); href is the no-JS
+			// fallback to the detail page, so nothing becomes JS-only.
+			<div class="card-title">
+				<a
+					href={ videoURL(r.VideoID) }
+					hx-get={ string(expandURL(r.VideoID)) }
+					hx-target={ "#video-" + r.VideoID }
+					hx-swap="outerHTML"
+				>{ displayTitle(r) }</a>
+			</div>
 		} else {
 			<div class="card-title">{ displayTitle(r) }</div>
 		}
@@ -327,6 +336,32 @@ templ VideoCard(r store.SummaryRow) {
 	</li>
 }
 
+// expandedCard is a summarized list card opened IN PLACE (ADR-031): the full
+// summary body + the deeper-dive chat dock, with a collapse control back to the
+// compact card. It shares the <li id> with VideoCard so HTMX swaps it outerHTML,
+// and reuses summaryBody + chatReveal so it never drifts from the detail page.
+// Note: chatReveal uses a single #chat-section id, so this assumes one card open
+// at a time; a per-video chat id is a follow-up if simultaneous expansion is wanted.
+templ expandedCard(r store.SummaryRow, chatEnabled bool) {
+	<li class="card card-expanded" id={ "video-" + r.VideoID }>
+		<div class="card-expanded-head">
+			<span class="card-title">{ displayTitle(r) }</span>
+			<a
+				href={ videoURL(r.VideoID) }
+				hx-get={ string(cardURL(r.VideoID)) }
+				hx-target={ "#video-" + r.VideoID }
+				hx-swap="outerHTML"
+				class="card-collapse"
+				title="Collapse"
+			>collapse ↑</a>
+		</div>
+		@summaryBody(r)
+		if chatEnabled {
+			@chatReveal(r.VideoID)
+		}
+	</li>
+}
+
 // TapirSpinner is the summarizing animation: a Charmbracelet-style TUI panel —
 // three richly coloured ASCII tapir frames (inline span colours, snout wiggling
 // ∩→∪→~) cross-faded by CSS, plus a lipgloss-style progress bar whose mint fill