fix(pdf): auto-install fonts missing from font fallbacks

[cderv]

When a font listed in monofontfallback (or any mainfont/sansfont/monofont fallback) is not installed, the PDF render fails and Quarto makes no attempt to auto-install the missing font.

Root Cause

luaotfload reports the missing fallback font as:

luaotfload | db : Reload initiated (formats: otf,ttf,ttc); reason: Font "DejaVu Sans Mono;-fallback" not found.

The packageMatchers in src/command/render/latexmk/parse-error.ts had no pattern for this format. The primary monofont case only works because fontspec also raises ! Package fontspec Error: The font "X" cannot be found, which is matched. The fallback path registers fonts via luaotfload.add_fallback(); when that fails, fontspec stays silent, so the unrecognized luaotfload message is the only signal.

luaotfload also appends ;-fallback internally to each fallback-chain entry. Left in place, the extracted name corrupts the tlmgr search-term regex.

Fix

Add a matcher for the luaotfload format and strip the ;-fallback suffix before building the search term. DejaVu Sans Mono then resolves to the dejavu CTAN package and auto-installs.

Test Plan

• Unit test in tests/unit/latexmk/parse-error.test.ts extracts the font name (suffix stripped) from the luaotfload log line
• Existing parse-error font cases still pass

Manual verification

Rendered a document with pdf-engine: lualatex, monofont: Latin Modern Mono, monofontfallback: [DejaVu Sans Mono] (uninstalled) and a glyph absent from the primary font, using a dev build with this change. The new matcher now fires where nothing did before:

finding package for DejaVu\s*Sans\s*Mono(-(Bold|Italic|Regular).*)?[.](tfm|afm|mf|otf|ttf)
> 1 package to install
> installing dejavu (1 of 1)

tlmgr then installs the dejavu package — the detection and auto-install path works as intended.

Note: completing the PDF still requires a fix outside this change. After the font is installed, luaotfload's fallback resolver looks up the literal suffixed name DejaVu Sans Mono;-fallback, fails, and aborts in luaotfload-fallback.lua even with the font present and its name database rebuilt. This is reproducible with bare lualatex and no Quarto involved, so it is tracked separately and does not affect the scope of this fix (recognizing the error format so auto-install is attempted).

Closes #14558

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