docs(bdd): scenarios for paste-a-URL + onboarding burst, mapped to tests

Adds paste_url.feature (valid/invalid/not-found/dedup, +@pending no-captions)
and an onboarding-burst scenario on connect; all non-pending scenarios mapped in
the coverage gate to their existing Go tests.

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

docs/use-cases/connect_account.feature

@@ -24,6 +24,12 @@ Feature: Connect and manage video accounts
     Then a discovery pass for my account is triggered right away
     And I do not have to wait for the next scheduled pass to see my videos
 
+  Scenario: Connecting summarizes my newest videos right away
+    Given I have no connected video accounts
+    When I connect my YouTube account
+    Then up to the onboarding cap of my newest videos are summarized through the rate gate
+    And the rest are left to the scheduled recency-bounded pass
+
   Scenario: Tokens are never stored in the clear
     When I connect any video account
     Then no OAuth token value is stored in the database

docs/use-cases/paste_url.feature

@@ -0,0 +1,30 @@
+Feature: Paste a YouTube URL to summarize any video
+  As a user
+  I want to paste a YouTube link and get a summary
+  So that I can pull the specific video I want now, even from channels I don't follow
+
+  Scenario: Paste a valid YouTube URL
+    Given I am connected
+    When I paste a valid YouTube video URL
+    Then the video is added to my feed scoped to me
+    And it is queued for summarization through the shared rate gate
+
+  Scenario: Pasting an invalid link is rejected
+    When I paste something that is not a YouTube video URL
+    Then I get a clear error and nothing is added
+
+  Scenario: Pasting a video that cannot be found is honest
+    When I paste a URL whose video cannot be found
+    Then I am told it couldn't be found and nothing is added
+
+  Scenario: Pasting the same video twice does not duplicate it
+    Given I have pasted a video
+    When I paste the same video again
+    Then my feed still has exactly one entry for it
+
+  @pending
+  # Covered by the engine's ADR-010 no-transcript terminal state (degrade-never-error);
+  # there is no paste-specific test for it.
+  Scenario: A pasted video with no captions resolves honestly
+    When I paste a video that has no captions
+    Then it resolves to the "no transcript available" terminal state

internal/web/paste_test.go

@@ -1,6 +1,11 @@
 package web
 
-import "testing"
+import (
+	"bytes"
+	"context"
+	"strings"
+	"testing"
+)
 
 func TestParseYouTubeVideoID(t *testing.T) {
 	const id = "dQw4w9WgXcQ"
@@ -55,3 +60,21 @@ func TestParseYouTubeVideoID(t *testing.T) {
 		})
 	}
 }
+
+func TestListPageShowsPasteFormOnlyWhenConnected(t *testing.T) {
+	render := func(connected bool) string {
+		var buf bytes.Buffer
+		if err := ListPage(listBuckets{}, Filter{}, PipelineStats{}, "", connected).Render(context.Background(), &buf); err != nil {
+			t.Fatalf("render: %v", err)
+		}
+		return buf.String()
+	}
+
+	html := render(true)
+	if !strings.Contains(html, `name="url"`) || !strings.Contains(html, `action="/paste"`) {
+		t.Errorf("connected feed must show the paste form")
+	}
+	if strings.Contains(render(false), `name="url"`) {
+		t.Errorf("disconnected feed must not show the paste form")
+	}
+}

internal/web/view.go

@@ -333,7 +333,7 @@ type flashView struct {
 // flashMessages maps each flash code to its banner. An unknown code renders no
 // banner (flashFor returns ok=false), so a forged cookie value is inert.
 var flashMessages = map[string]flashView{
-	flashConnected:     {"success", "YouTube account connected."},
+	flashConnected:     {"success", "YouTube account connected — finding your subscriptions. Your newest videos will appear below as they're summarized."},
 	flashConnectFailed: {"error", "Could not connect your YouTube account. Please try again."},
 	flashDisconnected:  {"success", "Account disconnected."},
 	flashDeleted:       {"success", "Your account and all its data were deleted."},

internal/web/views.templ

@@ -107,6 +107,9 @@ templ flashBanner(code string) {
 templ ListPage(b listBuckets, f Filter, stats PipelineStats, flash string, hasConnected bool) {
 	@Layout("Tapir — Summaries") {
 		@flashBanner(flash)
+		if hasConnected {
+			@pasteForm()
+		}
 		if !b.empty() || f.active() {
 			@filterForm(f)
 		}
@@ -143,6 +146,28 @@ templ pipelineBar(s PipelineStats) {
 	</div>
 }
 
+// pasteForm lets a connected user summarize any YouTube video by pasting its URL
+// (Feature 2). The result (a video card, or an inline error) swaps into
+// #paste-result; the next list refresh shows it inline. Summarization runs
+// through the shared caption rate gate like every other fetch.
+templ pasteForm() {
+	<form
+		class="paste"
+		method="post"
+		action="/paste"
+		hx-post="/paste"
+		hx-target="#paste-result"
+		hx-swap="innerHTML"
+	>
+		<label>
+			Summarize any video
+			<input type="url" name="url" placeholder="Paste a YouTube link…" required/>
+		</label>
+		<button type="submit">Add</button>
+	</form>
+	<div id="paste-result"></div>
+}
+
 templ filterForm(f Filter) {
 	<form
 		class="filters"

test/acceptance/scenario_coverage_test.go

@@ -37,9 +37,16 @@ var scenarioCoverage = map[string]string{
 	"An authenticated user on the welcome page sees their way in and out": "TestWelcomeLoggedIn",
 
 	// connect_account.feature
-	"Connect a YouTube account":                              "TestCallbackExchangesAndRecordsConnection",
-	"Connecting an account discovers videos immediately":     "TestCallbackTriggersDiscovery",
-	"Tokens are never stored in the clear":                   "TestCallbackExchangesAndRecordsConnection",
+	"Connect a YouTube account":                          "TestCallbackExchangesAndRecordsConnection",
+	"Connecting an account discovers videos immediately": "TestCallbackTriggersDiscovery",
+	"Connecting summarizes my newest videos right away":  "TestNewestUnsummarizedVideoIDs",
+	"Tokens are never stored in the clear":               "TestCallbackExchangesAndRecordsConnection",
+
+	// paste_url.feature
+	"Paste a valid YouTube URL":                              "TestPasteValidURLAddsAndRequests",
+	"Pasting an invalid link is rejected":                    "TestPasteInvalidURLRejected",
+	"Pasting a video that cannot be found is honest":         "TestPasteVideoNotFound",
+	"Pasting the same video twice does not duplicate it":     "TestPasteDedupNoDuplicate",
 	"Revoking a connection stops watching but keeps history": "TestDisconnectRemovesTokenAndConnectionKeepsAccount",
 
 	// summarize_mode.feature