Make the Compose mode's `Target file` semantics visible in two places:

- Placeholder: previously the generic `path/to/memories.md`. Now
  `~/.memtomem/memories/2026-04-30.md (leave blank for auto)` — the
  default location backend code in `add_memory()` already uses, with
  today's date computed at load time so the cue stays accurate.

- Add success toast: previously "Saved — N chunks indexed", agnostic to
  where the content went. Now "Saved to ~/.memtomem/memories/…/file.md
  — N chunks indexed", echoing the actual path returned by the API.

The placeholder is split into i18n prefix + `{date}` runtime + i18n
suffix to dodge the lang-toggle path: i18n.applyDOM rewrites
`data-i18n-placeholder` textContent on every switch and would otherwise
clobber a JS-templated value back to the raw `{date}` token. The input
keeps a static placeholder fallback (`~/.memtomem/memories/`) for the
sub-second window before settings-config.js's helper runs.

The toast path-tildify helper (`tildifyPath`) collapses the
host-specific `$HOME` prefix the server sends back to `~`. The browser
doesn't know `$HOME`, so the helper anchors on the `.memtomem/` segment
that backend write paths consistently use. Reused in #4.5a.

The deprecated `toast.saved_n_indexed` key is removed from both locales
(unused after this commit) and dropped from the i18n required-set test.

Co-Authored-By: Claude <[email protected]>

Upload silently writes to ~/.memtomem/uploads/, then on collision
suffixes the destination filename with the existing file's mtime
(system.py:862). Until now the success toast only said how many chunks
were indexed; users had no way to see where the file actually landed,
or that a rename had occurred.

Add `path: str | None = None` to UploadFileResult and have the upload
route echo the resolved `dest` (post-rename) so the client doesn't have
to guess. The toast prefers the new path-aware key
(`toast.upload_complete_with_path` — "Indexed N chunks → saved to
~/.memtomem/uploads/foo.md"), falling back to the count-only message if
no path is present (e.g., all-error batch). The path-tildify helper
introduced in the previous commit collapses $HOME to ~ for display.

The schema change is purely additive (new optional field, default
None), so existing callers and tests continue to work unchanged.

Co-Authored-By: Claude <[email protected]>

The "provider/model · backend" chip in the header is the only place
that surfaces the embedding pipeline and storage backend on every tab.
Users debugging "why is search slow" or "why are embeddings cleared"
have to recall that the matching settings live under Settings → Config
and click through manually.

Make the chip clickable: cursor changes on hover/focus, click +
keyboard activation (Enter/Space) navigate to Settings tab and select
the Config section. The tooltip now ends with "Open Embedding & Storage
settings" (i18n'd) and an aria-label exposes the same hint to screen
readers; both refresh on language toggle alongside the existing
detail lines (provider/model/dim, backend).

Co-Authored-By: Claude <[email protected]>

5 rows is enough to write a tag list, not enough to write the kind of
freeform memo people actually paste into Compose. Lift `min-height`
from 120 to 240 px (≈10 rows) so the textarea matches a real writing
surface; users can still drag the resize handle in either direction.

Co-Authored-By: Claude <[email protected]>

…579)

The Extensions/max-chunk hint at the bottom of the folder panel is read
as data (current config values), not as a callout that demands the
user's attention. Inheriting the shared .config-hint background +
border made it look heavier than the surrounding inputs.

Override the styling for `#index-config-hint` only (the home and
namespace hints — `#home-config-info`, `#ns-config-info` — keep their
existing chrome) to a plain muted line, and add the ⓘ marker via CSS
`::before` so it's single-source-of-truth in the stylesheet regardless
of which writer populates `textContent`.

Co-Authored-By: Claude <[email protected]>

"Target file" alone reads as if it could be a path on disk, on the
filesystem, or a virtual id — the user has no anchor for what's being
asked of them. Append "(save location)" / "(저장 위치)" to the label so
the placeholder hint and saved-path toast (introduced earlier in this
bundle) reinforce the same idea: this input controls where the memory
is stored under ~/.memtomem/memories/.

Markup unchanged — just an i18n string update in both locales.

Co-Authored-By: Claude <[email protected]>

Several JS-owned dynamic strings populate via listeners — Compose
placeholder (settings-config.js _refreshAddFilePlaceholder) and the
header-chip aria-label / jump-hint title (_syncHeaderConfig) — read
t() at the moment they run. settings-config.js's module-level
fetchServerConfig() can race ahead of app.js's `await I18N.init()`, so
those listeners can fire before the locale cache is populated and end
up writing the raw i18n key (e.g. `index.add_file_placeholder_prefix`)
to user-visible UI. Surfaced by the smoke for #579: the Compose
placeholder showed `index.add_file_placeholder_prefix2026-04-30
index.add_file_placeholder_suffix` and the header chip's aria-label
held `header.sys_info_jump_title` until the user toggled language.

Have I18N.init() dispatch a single langchange event after the locale
cache is filled. The same listeners then re-read t() with real
translations and overwrite their stale raw-key state. The bumped query
string on i18n.js (?v=2 → ?v=3) busts browser disk cache so the new
init body actually loads.

Co-Authored-By: Claude <[email protected]>