Feature/improving namespaces

[tamercuba]

Summary

• Namespace system: introduced NamespaceRegistry with risp.internal → risp.core → user chain; all Rust builtins are now private to risp.internal
• Risp stdlib (core.risp): builtins aliased via (def + risp.internal/+) pattern; map, filter, reduce, some, every?, print, println implemented in risp
• Qualified symbols (ns/name): parser, sema, and interpreter support for risp.core/map, risp.internal/+, etc. — including operator names like risp.internal//
• and/or special forms with short-circuit evaluation
• Named closures: defn injects the name into the closure; anonymous fn stays None
• String escape sequences: \n, \t, \r, \, " handled in the lexer
• Bug fixes: " escape guard, double-wrapping in Value::Display for Callable, qualified symbol parsing for / operator

Test plan

• All 399 unit tests pass
• cargo showcase renders output correctly (newlines, escapes)
• Qualified var resolution: risp.core/map, risp.internal/+, user/x
• and/or short-circuit (undefined var not evaluated)
• Named closure: (defn foo [x] x) (str foo) → "#"
• String escapes: "\n", "\t", """, "\"

[codacy-production]

Up to standards ✅

🟢 Issues 0 issues

Results:
0 new issues

View in Codacy

🟢 Metrics 0 complexity · -2 duplication

Metric	Results
Complexity	0
Duplication	-2

View in Codacy

🟢 Coverage 80.80% diff coverage · +0.14% coverage variation

Metric	Results
Coverage variation	✅ +0.14% coverage variation (-1.00%)
Diff coverage	✅ 80.80% diff coverage

View coverage diff in Codacy

Coverage variation details

	Coverable lines	Covered lines	Coverage
Common ancestor commit (70781cc)	3677	3230	87.84%
Head commit (2ded88e)	3894 (+217)	3426 (+196)	87.98% (+0.14%)

Coverage variation is the difference between the coverage for the head and common ancestor commits of the pull request branch: <coverage of head commit> - <coverage of common ancestor commit>

Diff coverage details

	Coverable lines	Covered lines	Diff coverage
Pull request (#17)	276	223	80.80%

Diff coverage is the percentage of lines that are covered by tests out of the coverable lines that the pull request added or modified: <covered lines added or modified>/<coverable lines added or modified> * 100%

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