[cfsmp3]

In raising this pull request, I confirm the following (please check boxes):

Reason for this PR:

• This PR adds new functionality.
• This PR fixes a bug that I have personally experienced or that a real user has reported and for which a sample exists.
• This PR is porting code from C to Rust.

Sanity check:

• I have read and understood the contributors guide.
• I have checked that another pull request for this purpose does not exist.
• If the PR adds new functionality, I've added it to the changelog. If it's just a bug fix, I have NOT added it to the changelog.
• I am NOT adding new C code unless it's to fix an existing, reproducible bug.

Repro instructions:

On master, any of these fails with Unknown Argument (exit 7) on any input, e.g. ccextractor input.ts -nofc:
-bi -nobi --nobufferinput -ff -bs -nofc --nofontcolor --nohtmlescape -nots --notypesetting -ntm --no-timestamp-map -nocodec -nospupngocr --transcript --timedtranscript -ve -gt -nogt --nogoptime -fp --norollup -key --gui_mode_reports --no_progress_bar -sbs -caf -pn -dc -scr -nolevdist -anvid -investigate_packets -nosync -haup -poc -tcppassword -tcpdesc -tickertape -ocr_mode -sub_color -min_sub_duration -detect_italics -conf_thresh -whiteness_thresh -lum_thresh

---

Follow-up to #2368. The v0.94 C parser accepted these spellings; the Rust parser rejects them, so old scripts and frontends break. #2368 covered nine; this covers the remaining 46 that still have an equivalent option.

• Each spelling is a hidden clap alias on the option with the same behaviour (checked against the v0.94 params.c and parser.rs), so --help is unchanged and normalize_legacy_args still skips option values.
• -ntm / --no-timestamp-map: v0.94 wrote WebVTT's X-TIMESTAMP-MAP header by default and this turned it off. The header is now off unless --timestamp-map is given, so these are accepted as a hidden no-op (and conflict with --timestamp-map).
• -pn needs a value now; v0.94 also allowed a bare -pn for autodetect.
• Not mapped: -enable-sharing, -sharing-url, -sharing-debug, -translate, -translate-auth — the sharing/translation feature no longer exists, so accepting them would silently do nothing. -curlposturl already works in libcurl builds, as in v0.94.

Verified:

• New tests: every mapped spelling parses to exactly the same Args as its modern spelling; the removed-feature spellings stay rejected; a legacy-looking option value is not rewritten. They fail without the change.
• --help is byte-identical to master.
• End to end, each of the 46 legacy spellings gives byte-identical output and exit code to its modern spelling.
• 24 local samples × 5 option sets: identical to master, except the set using -nofc, which master rejects and which now matches --no-fontcolor.