docs(books): mark the live parameters, give the card its column back

[kfox]

PR 5 of 8 in the reference-guide review stack, on top of #200–#203 (all merged, so this branches from main).

The introduction's Notation section promised that a parameter marked live could be moved during a show. Nothing was marked anywhere. Two different powers wear that word, so this marks them apart.

Appendices A and B: two marks

• *Live-tunable* — a MIDI knob, a pad or the web console can move it mid-show; the mark names the target string that reaches it, so [color].dither_strength says mode.dither_strength.
  The join is an explicit alias map, not a bare-name match: [color].dither is mode.dither_method (a name match would miss it), and a name match would also mark [audio].dither, which is the 4-bit DAC's noise shaping and has nothing to do with the display pipeline. A test resolves both ends of every entry, and asserts [audio].dither stays unmarked.
• *Menu-live* — FieldDoc.apply == "live", the metadata the on-C64 menu builds its panel from (overlays/menu.py), which was in the introspect model and read but never printed. Four scene keys carry it. A scene's palette_mode carries both, which is exactly why the two are worded apart.

The Notation section now says which is which; the on-C64 menu section in Chapter 6 points at the *menu-live* mark, so "which knobs does the panel offer" has an answer that is a property of the key rather than a list to maintain.

Appendix E: parameters spelled as targets

source.speed, not speed — the string a cc_map entry has to carry. A line can now be copied into a mapping unchanged, and it matches Appendix F's target column verbatim. A test pins every source.*/effect.* printed in Appendix E to a row Appendix F has.

The performance card gets Declared by back

The data was already in the LiveTargetDoc.owners tuple the card builder read and discarded. Raw owners will not fit a 3.5in column (source.speed has fourteen), so it compresses: the sole owner where there is one, otherwise a count in the group's noun — `moire2`, 14 generators, 3 modes — and all when the count equals the registry. Without the column a performer has no way to know that a knob mapped to source.ring_freq is dead unless moire2 is the generator on screen; 01-controls.md gains two lines saying how to read it.

Verification

• make lint typecheck clean; full suite 3307 tests OK.
• make reference-appendices && git diff --exit-code docs/ clean; --check reports all 10 generated files fresh.
• build_book.py --check passes for all three books; make books renders all three.
• Read the artefacts: the marks set correctly in the reference PDF (the "Appendix F" in each mark links through), Appendix E's holder-prefixed names still fit the fixed identity column, and the card is still two pages — the first draft of the 01-controls.md paragraph pushed it to three, so it was cut to two lines.

No hardware needed.