revert(motion): drop the legacy-file edits, keep the Astro ones

The motion pass edited five legacy files. Two changes were behaviour
regressions on the live site, and all five were out of scope: the brief
asks for an inventory of `src/`, and the legacy pages are what visitors
see until task 20 cuts over.

The confirmed break: `styles.css` changed the reading-progress bar to
`width:100%; transform:scaleX(0)`, but `app.js:406` still sets
`style.width = "N%"`. The inline width applies, the scaleX(0) is never
updated, and the bar renders at 0px on every legacy page. Verified in a
headless browser at 1100px, scrolled halfway: computed transform
`matrix(0, 0, 0, 1, 0, 0)`, bounding width `0`. The Astro island was
updated to set `transform` and is correct -- its half-scrolled bar
measures 595px -- so only the legacy half was broken.

The route-meter change (`height:var(--score)` to
`transform:scaleY(var(--score))` in `responsive.css`) does work:
`--score` is a percentage and Chromium accepts a percentage in
`scaleY()`. It is reverted anyway, because it belongs in the component.
`responsive.css` is being retired by task 15e, which is porting these
rules into the components that need them; that is where the meter should
stop animating a layout property. Noted in the 15e brief.

The three review-desk animations added to `skills-review/` are not
broken, but they change live-site behaviour ahead of the cutover and the
same motion already exists on the Astro side. Reverted for the same
reason.

Kept: every `src/` change -- the ReadingProgress transform, the guide
panel swap, the change-lens and package-preview easing, and the vote
widget tally pop.

skills-review/styles.css

@@ -15,4 +15,3 @@
 .markdown-preview{max-height:540px;overflow:auto;padding:24px;color:#d6e1e4;background:#0c1a25}.markdown-preview>:first-child{margin-top:0}.markdown-preview h1,.markdown-preview h2,.markdown-preview h3,.markdown-preview h4,.markdown-preview h5,.markdown-preview h6{margin:1.5em 0 .5em;color:#fff;line-height:1.15}.markdown-preview h1{font-size:1.8em}.markdown-preview h2{font-size:1.45em}.markdown-preview h3{font-size:1.2em}.markdown-preview p,.markdown-preview li{max-width:78ch}.markdown-preview li+li{margin-top:.35em}.markdown-preview a{color:var(--gold)}.markdown-preview code{padding:.12em .3em;color:#fff;background:#29455a;white-space:break-spaces}.markdown-preview pre{max-height:none;margin:1em 0;padding:14px;border:1px solid #486175}.markdown-preview pre code{padding:0;background:transparent}.markdown-preview blockquote{margin:1em 0;padding:.3em 1em;border-left:3px solid var(--gold);color:#b9c8d0}.markdown-preview hr{border:0;border-top:1px solid #486175}.markdown-frontmatter{display:grid;grid-template-columns:max-content 1fr;gap:3px 14px;margin:0 0 24px;padding:12px;border:1px solid #486175;font:11px/1.5 var(--font-mono)}.markdown-frontmatter dt{color:var(--gold)}.markdown-frontmatter dd{margin:0}.markdown-table-wrap{max-width:100%;overflow:auto;margin:1em 0;border:1px solid #486175}.markdown-preview table{width:100%;min-width:460px;border-collapse:collapse;font-size:13px}.markdown-preview th,.markdown-preview td{padding:9px 11px;border:1px solid #486175;text-align:left;vertical-align:top}.markdown-preview th{color:var(--gold);background:#173046}
 
 .markdown-toc{margin:0 0 24px;padding:12px 14px;border:1px solid #486175;background:#102b3a}.markdown-toc>span{color:var(--gold);font:700 10px var(--font-mono);letter-spacing:.1em}.markdown-toc ol{display:flex;flex-wrap:wrap;gap:7px 13px;margin:9px 0 0;padding:0;list-style:none}.markdown-toc li.level-2{margin-left:10px}.markdown-toc li.level-3{margin-left:20px}.markdown-toc a{font:12px/1.3 var(--font-sans);text-decoration:none}.markdown-toc a:hover{text-decoration:underline}
-.detail.is-swapping > * { /* purpose: review-desk detail swap on selection (state change) */ animation: detail-swap 200ms cubic-bezier(.2,0,0,1) both; } @keyframes detail-swap { from { opacity: 0.15; transform: translateY(5px); } to { opacity: 1; transform: translateY(0); } } .vote-buttons button b { display: inline-block; } .vote-buttons button b.is-updating { /* purpose: vote widget tally update (feedback) */ animation: tally-pop 200ms cubic-bezier(.2,0,0,1) both; } @keyframes tally-pop { from { opacity: 0; transform: translateY(-4px); } to { opacity: 1; transform: translateY(0); } } @media (prefers-reduced-motion: reduce) { .detail.is-swapping > *, .vote-buttons button b.is-updating { animation: none; } }