fix(theme): remove jQuery dependency from static JS

[AMD-melliott]

Issue

rocm_docs_theme's static JS — code_word_breaks.js, renameVersionLinks.js,
rdcMisc.js, and theme_mode_captions.js — references the jQuery global $,
but pydata-sphinx-theme (a rocm-docs-core dependency, currently pinned
>=0.15.4) hasn't shipped jQuery since it was dropped upstream in v0.13.0
(Feb 2023, [pydata/pydata-sphinx-theme#1029],
"Drop jQuery and use Bootstrap 5"). Every page load throws
ReferenceError: $ is not defined from all four files.

I noticed these errors when testing via Playwright-based console validation during the instinct-design flavor development.

Fix

Rewrote all four files to plain DOM APIs, no jQuery:

• code_word_breaks.js / renameVersionLinks.js — mechanical translation to
  querySelectorAll/classList/native event listeners, same behavior.
• rdcMisc.js — breadcrumb truncation math needed adjusting along the way:
  jQuery's .width()/.height() always normalized to content-box, while
  getComputedStyle() reflects box-sizing: border-box under
  pydata-sphinx-theme's Bootstrap 5 reset, which was inflating measured width
  and shifting the truncation threshold. Now computed via
  getBoundingClientRect() minus padding/border to match the original
  content-box semantics.
• theme_mode_captions.js — drops the $(window).ajaxComplete(...) handler;
  there's no jQuery-driven AJAX left in this environment for it to observe,
  and the existing click listener already keeps the caption in sync on
  user-initiated theme toggles.

Scope / risk

A repo-wide check confirms these are the only four files in
rocm_docs_theme's own static assets referencing jQuery syntax — search.js
and the newer instinct-design.js are already jQuery-free. All four affected
behaviors are cosmetic UX affordances (code-cell copy + word-break
formatting, version-dropdown label cleanup, breadcrumb truncation + sidebar
auto-collapse, theme-toggle tooltip caption) — none touch search, navigation,
or content rendering, so functional risk from the rewrite is low.

A secondary bootstrap.js getBoundingClientRect TypeError reported
alongside this is from pydata-sphinx-theme's own vendored Bootstrap bundle,
not this theme's code — out of scope here; worth a separate upstream report
against pydata-sphinx-theme if it still reproduces once this lands.

Verification

Exercised via a standalone HTML harness with representative
breadcrumb/table/version-dropdown/theme-switch markup, run through Playwright
in a headless browser: zero console errors, and all four behaviors confirmed
working (click-to-copy, word-break insertion, breadcrumb truncation,
version-link renaming, theme-mode caption update).