insight-chat: code-review polish on the system-prompt split

- Use Option::map instead of manual match-on-Option (drops clippy::manual_map).
- Drop redundant `max_iterations = max_iterations` from the format! call.
- Use captured identifiers consistently in the user_content format!.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/ai/insight_generator.rs

@@ -2980,7 +2980,6 @@ Return ONLY the summary, nothing else."#,
              - Use recall_facts_for_photo + recall_entities to load any prior knowledge about subjects in the photo.\n\
              - When you identify people / places / events / things, use store_entity + store_fact to grow the persistent memory.\n\
              - A tool returning no results is informative; continue with the others.",
-            max_iterations = max_iterations
         );
 
         let mut out = identity;
@@ -3344,8 +3343,8 @@ Return ONLY the summary, nothing else."#,
         // (when supplied) is the authoritative identity — the framework
         // never appends a competing "you are a personal photo memory
         // assistant" line. The procedural block stays identity-free.
-        let owner_id_note = match owner_entity_id {
-            Some(id) => Some(format!(
+        let owner_id_note = owner_entity_id.map(|id| {
+            format!(
                 "\n\nYour identity in the knowledge store: {name} (entity ID: {id}). \
                 When storing facts where you ({name}) are the object — for example, someone is your friend, \
                 sibling, or colleague — use subject_entity_id for the other person and set object_value to \
@@ -3353,9 +3352,8 @@ Return ONLY the summary, nothing else."#,
                 {name} directly, use {id} as the subject_entity_id.",
                 name = owner_name,
                 id = id
-            )),
-            None => None,
-        };
+            )
+        });
         let fewshot_block = Self::render_fewshot_examples(&fewshot_examples);
         let system_content = Self::build_system_content(
             custom_system_prompt.as_deref(),
@@ -3397,18 +3395,13 @@ Return ONLY the summary, nothing else."#,
         // and summary" claim that used to live here was unused (the title is
         // regenerated post-hoc from the summary by generate_photo_title).
         let user_content = format!(
-            "{visual_block}Photo file path: {}\n\
-             Date taken: {}\n\
-             {}\n\
-             {}\n\
-             {}\n\n\
+            "{visual_block}Photo file path: {file_path}\n\
+             Date taken: {date}\n\
+             {contact_info}\n\
+             {gps_info}\n\
+             {tags_info}\n\n\
              Gather context with the available tools, then respond.",
-            file_path,
-            date_taken.format("%B %d, %Y"),
-            contact_info,
-            gps_info,
-            tags_info,
-            visual_block = visual_block,
+            date = date_taken.format("%B %d, %Y"),
         );
 
         // 10. Define tools. Hybrid mode omits `describe_photo` since the