Add template:insert error message to docs

Clarifies exact error returned when no file is active in Obsidian UI:
"Error: No active editor. Open a file first."

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

plugins/obsidian-cli/skills/obsidian-cli/SKILL.md

@@ -210,7 +210,7 @@ obsidian sync:restore path="important.md" version=3  # Rollback
 6. **Stderr noise** — GPU/Electron warnings on headless are harmless; filter with `2>/dev/null`.
 7. **`daily:prepend`** inserts content after frontmatter, not at byte 0.
 8. **Use `eval`** to run arbitrary JavaScript against the Obsidian API (`app.*`).
-9. **`template:insert`** inserts into the currently active file in the Obsidian UI — it does not accept a `path=` parameter. To create a file from a template via CLI, use `obsidian create path="..." template="..."` instead.
+9. **`template:insert`** inserts into the currently active file in the Obsidian UI — it does not accept a `path=` parameter. If no file is open, it returns `Error: No active editor. Open a file first.` To create a file from a template via CLI, use `obsidian create path="..." template="..."` instead.
 
 ## Troubleshooting
 

plugins/obsidian-cli/skills/obsidian-cli/references/command-reference.md

@@ -257,7 +257,7 @@ obsidian template:insert name="weekly-review"           # Insert template into t
 - `resolve` — Process template variables (`{{date}}`, `{{title}}`, etc.)
 - Title and other variables can be passed as `key=value` for template rendering.
 
-> **Note:** `template:insert` inserts into whichever file is currently active in the Obsidian UI — it does not accept a `path=` parameter. To create a new file from a template, use `obsidian create path="..." template="..."` instead.
+> **Note:** `template:insert` inserts into whichever file is currently active in the Obsidian UI — it does not accept a `path=` parameter. If no file is open, it returns `Error: No active editor. Open a file first.` To create a new file from a template, use `obsidian create path="..." template="..."` instead.
 
 ---
 

skills/obsidian-cli/SKILL.md

@@ -210,7 +210,7 @@ obsidian sync:restore path="important.md" version=3  # Rollback
 6. **Stderr noise** — GPU/Electron warnings on headless are harmless; filter with `2>/dev/null`.
 7. **`daily:prepend`** inserts content after frontmatter, not at byte 0.
 8. **Use `eval`** to run arbitrary JavaScript against the Obsidian API (`app.*`).
-9. **`template:insert`** inserts into the currently active file in the Obsidian UI — it does not accept a `path=` parameter. To create a file from a template via CLI, use `obsidian create path="..." template="..."` instead.
+9. **`template:insert`** inserts into the currently active file in the Obsidian UI — it does not accept a `path=` parameter. If no file is open, it returns `Error: No active editor. Open a file first.` To create a file from a template via CLI, use `obsidian create path="..." template="..."` instead.
 
 ## Troubleshooting
 

skills/obsidian-cli/references/command-reference.md

@@ -257,7 +257,7 @@ obsidian template:insert name="weekly-review"           # Insert template into t
 - `resolve` — Process template variables (`{{date}}`, `{{title}}`, etc.)
 - Title and other variables can be passed as `key=value` for template rendering.
 
-> **Note:** `template:insert` inserts into whichever file is currently active in the Obsidian UI — it does not accept a `path=` parameter. To create a new file from a template, use `obsidian create path="..." template="..."` instead.
+> **Note:** `template:insert` inserts into whichever file is currently active in the Obsidian UI — it does not accept a `path=` parameter. If no file is open, it returns `Error: No active editor. Open a file first.` To create a new file from a template, use `obsidian create path="..." template="..."` instead.
 
 ---