Implements 8 new language features:
- |> pipe operator: a |> f desugars to f(a), left-associative chains
- with record update: let b = a with { field: val } — non-destructive struct update
- retry/fallback: retry N times { ... } fallback { ... } with counter-based loop codegen
- reason: AI inference primitive calling soma /v1/chat/completions at runtime
- parallel: concurrent execution block returning a Map of named results via threads
- trace: zero-cost observability block emitting TraceBegin/TraceEnd with ms timing
- requires: precondition annotation on fn, emits ContractCheck bytecode at entry
- deploy: deployment-as-syntax posting to soma /v1/deploy at runtime
All features thread through lexer → parser/AST → codegen → runtime interpreter.
- Register print/println/log/print_err in TypeEnv::with_builtins() with polymorphic (Unknown) param type so any value type is accepted without spurious warnings
- Add StructLit expr to AST + parser (uppercase-IDENT { ... } syntax), BuildStruct bytecode instruction + Struct value to runtime
- Add type_params to FnDef AST node and TypeParam variant to TypeExpr; parser parses <T, E> generics; type checker treats TypeParam as Unknown (universal type)
- Rewrite interpreter to support user-defined function calls via call stack (Frame + return_ip); dispatch_builtin handles print/println/log/print_err/__build_list__
- Fix engram_activate_search to unwrap { results: [...] } response envelope from /search; use std::net for sync HTTP to avoid reqwest dependency
- Add run-file command to CLI for single-file execution without el.toml
- Fix worktree engram-crypto path dep