feat(templates): NoteTemplate catalog + apply in to_markdown (T8.1, FR-NOTE-5)

4 built-in templates (Standup, 1:1, Sales Call, Retro), keyed by the
same meeting-type ids commands::summary_prompt_bias already uses for
LLM-prompt biasing — one identifier space shared by both, but two
independent lookups (structuring notes.md vs. biasing a summary
prompt). Section headers are prepended as an empty scaffold above the
auto-rendered speaker dialogue.

src-tauri/src/notes/mod.rs

@@ -5,6 +5,7 @@
 
 use crate::models::{SpeakerInfo, TranscriptSegment};
 use pulldown_cmark::{Event, HeadingLevel, Options, Parser, Tag, TagEnd};
+use serde::{Deserialize, Serialize};
 use std::path::{Path, PathBuf};
 
 #[derive(Debug, thiserror::Error)]
@@ -25,13 +26,73 @@ pub enum ExportFormat {
     Bundle, // audio + transcript + notes
 }
 
+/// A note template (Phase 8, T8.1, FR-NOTE-5) — section headers prepended
+/// to `to_markdown`'s output, giving the user a scaffold to fill in by hand
+/// above the auto-rendered speaker dialogue. Distinct from
+/// `commands::summary_prompt_bias`, which biases the *LLM summary prompt*
+/// for the same meeting-type identifiers rather than structuring notes.md.
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct NoteTemplate {
+    pub id: String,
+    pub name: String,
+    pub sections: Vec<String>,
+}
+
+/// Built-in templates, keyed by the same ids `commands::summary_prompt_bias`
+/// already uses for its LLM-prompt biasing ("standup"/"retro"/"one-on-one"),
+/// plus "sales-call" per FR-NOTE-5's example — one meeting-type identifier
+/// space shared by both features.
+pub fn built_in_note_templates() -> Vec<NoteTemplate> {
+    vec![
+        NoteTemplate {
+            id: "standup".to_string(),
+            name: "Standup".to_string(),
+            sections: vec![
+                "Yesterday".to_string(),
+                "Today".to_string(),
+                "Blockers".to_string(),
+            ],
+        },
+        NoteTemplate {
+            id: "one-on-one".to_string(),
+            name: "1:1".to_string(),
+            sections: vec!["Discussion".to_string(), "Action Items".to_string()],
+        },
+        NoteTemplate {
+            id: "sales-call".to_string(),
+            name: "Sales Call".to_string(),
+            sections: vec![
+                "Agenda".to_string(),
+                "Discussion".to_string(),
+                "Next Steps".to_string(),
+            ],
+        },
+        NoteTemplate {
+            id: "retro".to_string(),
+            name: "Retro".to_string(),
+            sections: vec![
+                "What Went Well".to_string(),
+                "What Didn't".to_string(),
+                "Action Items".to_string(),
+            ],
+        },
+    ]
+}
+
+pub fn note_template_by_id(id: &str) -> Option<NoteTemplate> {
+    built_in_note_templates().into_iter().find(|t| t.id == id)
+}
+
 pub trait NotesRenderer: Send + Sync {
     /// Build Markdown with speaker-tagged dialogue (+ summary if present).
+    /// `template`'s section headers (if any) are prepended as an empty
+    /// scaffold for the user to fill in above the dialogue.
     fn to_markdown(
         &self,
         segments: &[TranscriptSegment],
         speakers: &[SpeakerInfo],
         summary_md: Option<&str>,
+        template: Option<&NoteTemplate>,
     ) -> String;
 
     fn export(&self, markdown: &str, dest: &Path, fmt: ExportFormat)
@@ -46,8 +107,14 @@ impl NotesRenderer for MarkdownNotes {
         segments: &[TranscriptSegment],
         speakers: &[SpeakerInfo],
         summary_md: Option<&str>,
+        template: Option<&NoteTemplate>,
     ) -> String {
         let mut out = String::new();
+        if let Some(template) = template {
+            for section in &template.sections {
+                out.push_str(&format!("## {section}\n\n"));
+            }
+        }
         if let Some(summary) = summary_md {
             let summary = summary.trim();
             if !summary.is_empty() {
@@ -246,7 +313,7 @@ mod tests {
             seg(1, "S1", "world."),
             seg(2, "S2", "Hi there."),
         ];
-        let md = MarkdownNotes.to_markdown(&segments, &[], None);
+        let md = MarkdownNotes.to_markdown(&segments, &[], None, None);
         assert_eq!(md, "**S1:** Hello world.\n\n**S2:** Hi there.");
     }
 
@@ -259,11 +326,11 @@ mod tests {
             participant_id: None,
         }];
         assert_eq!(
-            MarkdownNotes.to_markdown(&segments, &speakers, None),
+            MarkdownNotes.to_markdown(&segments, &speakers, None, None),
             "**Alex:** Hi"
         );
         assert_eq!(
-            MarkdownNotes.to_markdown(&segments, &[], None),
+            MarkdownNotes.to_markdown(&segments, &[], None, None),
             "**S1:** Hi"
         );
     }
@@ -271,10 +338,18 @@ mod tests {
     #[test]
     fn skips_blank_segments_and_prepends_summary() {
         let segments = vec![seg(0, "S1", "  "), seg(1, "S1", "Real text.")];
-        let md = MarkdownNotes.to_markdown(&segments, &[], Some("## Summary\nDone."));
+        let md = MarkdownNotes.to_markdown(&segments, &[], Some("## Summary\nDone."), None);
         assert_eq!(md, "## Summary\nDone.\n\n---\n\n**S1:** Real text.");
     }
 
+    #[test]
+    fn applies_template_sections_as_an_empty_scaffold_above_the_dialogue() {
+        let segments = vec![seg(0, "S1", "Hi")];
+        let template = note_template_by_id("one-on-one").unwrap();
+        let md = MarkdownNotes.to_markdown(&segments, &[], None, Some(&template));
+        assert_eq!(md, "## Discussion\n\n## Action Items\n\n**S1:** Hi");
+    }
+
     #[test]
     fn markdown_to_blocks_parses_heading_bold_prefix_and_task_list() {
         let md = "## Summary\n\n**Alice:** Hello world.\n\n- [ ] Follow up\n- [x] Done thing";