A personality belongs to a person

Owner's correction to 1.4.0: a model's character is per (model, person), and only
the description and the notes stay instance-wide. Two people talking to one model
are not talking to the same personality, and neither can see the other's.

The administrator's box becomes the DEFAULT, resolved by `personas.effective` as
a fallback and never as a layer -- two personalities at once contradict each
other with nothing to say which is losing, which is the reasoning behind "system
prompts replace, never stack". `persona_write` takes no argument naming a model
or a person; both come from the ToolContext, so it can only write the character
it has with whoever it is talking to, and it never touches the default.

Impressions move to their own table. Not a `kind` column: 1.4.0 shipped
`UNIQUE(model_key, owner_id)`, SQLite cannot alter a constraint and this schema
is additive-only, so a discriminator would leave an upgraded instance unable to
hold both rows for one pair. That leaves the first MANUAL_STEPS entry this
project has had -- the two shapes are indistinguishable, so nothing rewrites
them: a repair would be guessing at text that is read back in the first person.

TWO BUGS FROM A PHONE

`min-width` beats both `width` and `max-width` -- CSS clamps width to max-width
and then raises the result to min-width -- so `.canvas` and `.terminal` were
384px wide on every screen narrower than that, their `min(…, 100vw)` cap
overruled, and `.inspector` had no cap at all on a width that is a preference
draggable to 2400px. None of it scrolled sideways, because all three are
`position: fixed` and fixed overflow does not extend the scrollable area -- which
is exactly why the 1.1.0 narrow pass reported these pages clean. `min-width: 0`
in the overlay query, full width below the phone breakpoint, tablet column kept.

And the install button now says why it is absent. Measured against the live
instance: the manifest meets every Chrome criterion and the blocker is a
certificate from a private CA, so the origin is not trustworthy, the service
worker is refused and no install is offered. `base.html` had been swallowing that
with an empty catch -- which kept the page working, the reason it was there, and
threw away the only evidence. It now records the outcome and `app.js` turns it
into a sentence naming the certificate, which is the cause the old hint did not
mention.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

tests/test_layout_bounds.py

@@ -119,3 +119,92 @@ def test_no_breakpoint_is_declared_and_never_used():
     assert declared <= _breakpoints_used(), (
         f"declared and unused: {sorted(declared - _breakpoints_used())}"
     )
+
+
+# --- A minimum wider than the screen -----------------------------------------
+#
+# A panel's `--*-width-min` is there so a dragged edge cannot be pulled to
+# nothing on a desktop. On a phone it was the bug: `min-width` is resolved after
+# `width` and `max-width` and **wins over both** -- CSS clamps width to max-width
+# and then raises the result to min-width -- so
+# `.canvas { width: min(var(--canvas-width), 100vw) }` inside the narrow query was
+# simply overruled by `min-width: 24rem`, and both side panels were 384px wide on
+# every screen narrower than that. `.inspector` had no cap at all, and its width
+# is a *preference* somebody can drag to 2400px.
+#
+# Nothing scrolled sideways, because all three are `position: fixed` and fixed
+# overflow does not extend the scrollable area. So the symptom was content off
+# the edge of the screen and unreachable, which is exactly what a pass looking
+# for sideways scrolling does not find.
+#
+# This is the tree's standing rule in another shape: a track's minimum wider than
+# the viewport is the bug, and the minimum is the thing that has to give.
+APP_CSS = (ROOT / "web/static/css/app.css").read_text(encoding="utf-8")
+
+# Every panel that becomes an overlay rather than a column on a small screen.
+OVERLAY_PANELS = (".inspector", ".terminal", ".canvas")
+
+
+def _media_body(css: str, condition: str) -> str:
+    """The contents of every `@media` block whose condition matches, joined.
+
+    Braces are balanced rather than split on, because taking everything after
+    `@media` gives the rest of the file -- a test written that way asserts about
+    the whole stylesheet while appearing to be about one query.
+    """
+    bodies = []
+    for start in (i for i in range(len(css)) if css.startswith("@media", i)):
+        opened = css.index("{", start)
+        if condition not in css[start:opened]:
+            continue
+        depth, cursor = 0, opened
+        while cursor < len(css):
+            if css[cursor] == "{":
+                depth += 1
+            elif css[cursor] == "}":
+                depth -= 1
+                if depth == 0:
+                    break
+            cursor += 1
+        bodies.append(css[opened + 1 : cursor])
+    return "\n".join(bodies)
+
+
+def test_the_scan_finds_both_queries():
+    """A blindness guard: if either breakpoint is renamed, the two tests below
+    would pass by asserting about an empty string."""
+    assert _media_body(APP_CSS, "64rem").strip()
+    assert _media_body(APP_CSS, "48rem").strip()
+
+
+def test_no_overlay_panel_keeps_a_minimum_once_it_is_an_overlay():
+    """The fix, stated as the property rather than as the declaration: inside the
+    query where these become fixed overlays, nothing may hold them wider than the
+    screen. `min-width: 0` is how that is written."""
+    body = _media_body(APP_CSS, "64rem")
+    assert "min-width: 0" in body, (
+        "the overlay panels have no `min-width: 0`, so `--*-width-min` wins again "
+        "and a panel is wider than a narrow screen"
+    )
+    for panel in OVERLAY_PANELS:
+        assert panel in body, f"{panel} is no longer part of the overlay query"
+
+
+def test_every_overlay_panel_is_full_width_on_a_phone():
+    """A 20% sliver of conversation behind a sheet is not a view of anything, so
+    below the phone breakpoint the panels take the whole width. The tablet keeps
+    its column, which is why this is asserted on the 48rem query and not the
+    64rem one."""
+    body = _media_body(APP_CSS, "48rem")
+    for panel in OVERLAY_PANELS:
+        assert panel in body, f"{panel} is not sized on a phone"
+    assert "width: 100vw" in body
+    assert "max-width: 100vw" in body
+
+
+def test_the_desktop_minimum_is_still_declared():
+    """The other direction. Removing the minimum altogether would let a drag
+    handle pull a panel to nothing on the machine where dragging exists."""
+    for token in ("--terminal-width-min", "--canvas-width-min"):
+        assert f"{token}:" in TOKENS
+        assert f"var({token})" in APP_CSS