feat(cli): support multi-line status line output (#3311)

* feat(cli): support multi-line status line output (#3211)

Remove the single-line hard limit (.split('\n')[0]) from the status line
hook so user scripts can output multiple rows. Footer renders each line
as a separate <Text wrap="truncate"> element, preserving per-line
horizontal truncation. Ink's virtual DOM handles re-rendering without
manual ANSI cursor management.

* feat(cli): cap status line output at 3 lines

Prevent runaway scripts from flooding the footer — lines beyond the
third are silently discarded.

* docs: mention 3-line cap in status line docs and agent prompt

* fix(cli): cap status line at 2 lines to keep footer within 3 rows

Footer has a fixed bottom row (hint/mode indicator), so status line
gets at most 2 lines to keep the total footer height at 3 rows max.

* test(cli): improve useStatusLine coverage to 100% lines

Add tests for: per-model metrics payload, contextWindowSize/version/
model fallbacks, config removal with pending debounce, command change
cancelling pending debounce.

* docs: update status line ASCII diagram for multi-line layouts

Also fix TS error in test (null → null as never for mock return).

* refactor(cli): return string[] from useStatusLine, filter empty lines

Address review feedback:
- Hook returns `lines: string[]` instead of `text: string | null`,
  eliminating the join/split round-trip with Footer.
- Filter empty lines before slicing so leading blanks don't eat real
  content (e.g. "\n\nreal content" no longer yields ["", ""]).
- Export MAX_STATUS_LINES with comment explaining the 3-row constraint.
- Use `status-line-${i}` as React key for clarity.

* test(cli): add Footer multi-line rendering, \r\n, and pure-newline tests

Address remaining review feedback:
- Footer test: mock useStatusLine, verify multi-line rendering and
  hint suppression.
- useStatusLine test: add \r\n line ending and pure-newline edge case.

* fix(cli): align right footer indicators to top

When the status line has multiple rows, the left column becomes taller
than the right section. The outer Box defaults to `alignItems: stretch`
which caused the indicators to visually center; add `alignItems="flex-start"`
on the right Box so they stay anchored to the top row.

Reported via e2e test in #3311.

docs/users/features/memory.md

@@ -2,7 +2,7 @@
 
 Every Qwen Code session starts with a fresh context window. Two mechanisms carry knowledge across sessions so you don't have to re-explain yourself every time:
 
-- **QWEN.md** — instructions *you* write once and Qwen reads every session
+- **QWEN.md** — instructions _you_ write once and Qwen reads every session
 - **Auto-memory** — notes Qwen writes itself based on what it learns from you
 
 ---
@@ -24,9 +24,9 @@ Don't include things Qwen can figure out by reading your code. QWEN.md works bes
 
 ### Where to create QWEN.md
 
-| File | Who it applies to |
-|---|---|
-| `~/.qwen/QWEN.md` | You, across all your projects |
+| File                          | Who it applies to                             |
+| ----------------------------- | --------------------------------------------- |
+| `~/.qwen/QWEN.md`             | You, across all your projects                 |
 | `QWEN.md` in the project root | Your whole team (commit it to source control) |
 
 You can have both. Qwen loads all QWEN.md files it finds when you start a session — your personal one plus any in the project.
@@ -45,6 +45,7 @@ You can point QWEN.md at other files so Qwen reads them too:
 See @README.md for project overview.
 
 # Conventions
+
 - Git workflow: @docs/git-workflow.md
 ```
 
@@ -62,12 +63,12 @@ This is different from QWEN.md: you don't write it, Qwen does.
 
 Qwen looks for four kinds of things worth remembering:
 
-| What | Examples |
-|---|---|
-| **About you** | Your role, background, how you like to work |
-| **Your feedback** | Corrections you made, approaches you confirmed |
-| **Project context** | Ongoing work, decisions, goals not obvious from the code |
-| **External references** | Dashboards, ticket trackers, docs links you mentioned |
+| What                    | Examples                                                 |
+| ----------------------- | -------------------------------------------------------- |
+| **About you**           | Your role, background, how you like to work              |
+| **Your feedback**       | Corrections you made, approaches you confirmed           |
+| **Project context**     | Ongoing work, decisions, goals not obvious from the code |
+| **External references** | Dashboards, ticket trackers, docs links you mentioned    |
 
 Qwen doesn't save everything — only things that would actually be useful next time.
 
@@ -150,6 +151,7 @@ Runs the memory cleanup now instead of waiting for the automatic schedule:
 Open `/memory` to see which files are loaded. If your file isn't listed, Qwen can't see it — make sure it's in the project root or `~/.qwen/`.
 
 Instructions work better when they're specific:
+
 - ✓ `Use 2-space indentation for TypeScript files`
 - ✗ `Format code nicely`