Protocol method declarations now declare their receiver explicitly as the first
parameter — 'self: *Self' (or 'self: Self') — matching the impl method signature,
instead of the old implicit-receiver form where the listed params were only the
extra args. That asymmetry repeatedly caused confusion over whether the first
param was the receiver or an argument.
The parser validates the first param is 'self' typed Self/*Self, then strips it,
so all downstream lowering and the dispatch ABI are unchanged (impl blocks and
call sites are unaffected). A protocol method missing the receiver is now a parse
error.
Migrated all 129 protocol method signatures across library + examples (+ one
inline-sx test in sema.zig) to the explicit form. Updated specs.md + readme.md.
New: examples/0418-protocols-explicit-receiver.sx (feature),
examples/1190-diagnostics-protocol-missing-receiver.sx (negative/diagnostic).
`registerProtocolDecl` resolved each method's param/return type NAME
through the flat, visibility-unaware `type_bridge.resolveAstType`, so a
type name colliding across modules bound to the wrong author. In the
repro the user's `Event` enum collides with the stdlib `event.Event`
struct (pulled in by `modules/std.sx`): the protocol grabbed the stdlib
struct, typed an inferred `g_plat.one_event()` as a fieldless struct,
bound the `case .key_up:(e)` payload to `.unresolved`, and emitted
"enum literal '.escape' has no destination type to resolve against".
Resolve both param and return types through
`resolveTypeInSource(pd.source_file, …)` — the visibility-aware resolver
pinned to the protocol's own declaring module, keeping the `Self → *void`
short-circuit. Brings the non-parameterized path to parity with
`instantiateParamProtocol` and concrete-fn signatures. No silent default:
not-visible / ambiguous names still diagnose and poison with `.unresolved`.
Closes issue 0132 — the protocol-return case left open by f13f4ab (which
fixed the enum/union/inline/error-set registration class). Regression
test: examples/0417-protocols-protocol-return-name-collision.sx.
