feat(parser): compound player+object hexproof/shroud static — generalise You-and-X grants (CR 702.11 / CR 702.18 / CR 611.3a)

[claytonlin1110]

Summary

Generalize parse_compound_subject_keyword_static (currently Protection-only + hard-coded object subjects) into the full player + object compound keyword-grant class — the structural sibling of Serra's Emissary / #5219-style compound continuous statics.

Today the handler only claims:

• object subjects: creatures you control / other creatures you control / permanents you control
• player half: StaticMode::PlayerProtection only

Every other player+object grant falls through to a single incorrect Continuous that Ors the player filter with objects (empty typed + You), which layers interpret as granting the keyword to every permanent you control — including the wrong self-scope. That is the live Sigarda bug (Discord / #5322).

Class (not a card)

You and <object-subject> have <player-applicable keyword> where the keyword has a player-scope StaticMode:

Keyword	Object half	Player half
Protection from Q	Continuous + AddKeyword(Protection(Q))	PlayerProtection(Q)
Hexproof	Continuous + AddKeyword(Hexproof)	StaticMode::Hexproof
Shroud	Continuous + AddKeyword(Shroud)	StaticMode::Shroud

Object subjects must reuse parse_rule_static_subject_filter (subtype scopes, this creature / ~, other Heroes you control, etc.) — not a hard-coded alt of three phrases.

Gated forms of the same class:

• Leading turn window: During your turn, you and this creature have hexproof. (Gruul Spellbreaker)
• Inverted / trailing condition: As long as <cond>, you and other Heroes you control have hexproof. (Captain America, Super-Soldier)

Anchored on

• crates/engine/src/parser/oracle_static/evasion.rs parse_compound_subject_keyword_static — existing Protection splitter (Serra's Emissary)
• crates/engine/src/parser/oracle_static/grammar.rs lower_rule_static Hexproof/Shroud player-scope arms + static_you_have_hexproof / static_you_have_shroud
• Dispatch site: shared.rs parse_static_line_multi_dispatch (immediately before single-return fallback)

Same structural shape as #5219: dedicated compound handler before the incomplete single-subject sibling, reuse existing predicate/modification builders, Or/split scopes so one StaticDefinition is not forced to carry both player and object affected sets.

Example Oracle (Scryfall-verified)

• Sigarda, Heron's Grace: You and Humans you control have hexproof.
• I Am Untouchable: You and permanents you control have hexproof.
• Gruul Spellbreaker: During your turn, you and this creature have hexproof.
• Captain America, Super-Soldier: As long as Captain America has a shield counter on him, you and other Heroes you control have hexproof.
• Regression: Serra's Emissary Protection compound must keep splitting unchanged

Out of scope

Instant/sorcery until-EOT grants (Dawn's Truce, Lazotep Plating, Veil of Summer) — effect pipeline, not continuous statics.

Related

• Discord bug / needs-triage: Sigarda, Heron's Grace bug — Sigarda grants itself, and all creatures you control, hexproof despite not being a Human #5322 (Sigarda wrong self + all-creatures hexproof)
• Structural precedent: feat(parser): compound-subject animation static — Life and Limb (CR 611.3) #5219 compound-subject animation static

Acceptance

• Sigarda-class lines emit exactly two defs: object Continuous{AddKeyword(Hexproof)} with Human/controller filter, and player StaticMode::Hexproof on controller-You
• Wrong empty-typed Or / self-hexproof misparse is gone
• Protection compound regressions still pass
• Gate A (check-parser-combinators.sh) + oracle_static tests green