fix(assail): skip .ipkg files in Idris ProofDrift; add Chapel detector

Two deferred follow-ups from the 2026-04-25 echidna chunked sweep:

1. .ipkg ProofDrift false-positive (echidnaabi.ipkg)

   Idris2 package manifests share the `idr`/`ipkg` extension family
   and route through `analyze_idris`, but `.ipkg` is a TOML-like
   build config — not source.  String-literal mentions of banned
   pattern names (e.g. `brief = "...zero believe_me..."`) tripped
   the substring-based ProofDrift detector.

   Fix: short-circuit `analyze_idris` for files ending in `.ipkg`.
   Verified: src/abi sweep (echidna) drops to 0 ProofDrift findings.

2. Chapel language detector gap

   src/chapel returned `Could not detect language` because Chapel
   was missing from `Language` enum + extension map.

   Fix: add `Language::Chapel`, map `.chpl` extension, route through
   `analyze_generic` fallback (Chapel-specific patterns deferred —
   no Chapel-original code in echidna yet to dogfood against).

   Verified: src/chapel sweep (echidna) now produces a normal
   AssailReport with 6 Chapel-marked entries instead of erroring.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: hyperpolymath

src/assail/analyzer.rs

@@ -3280,6 +3280,15 @@ impl Analyzer {
         weak_points: &mut Vec<WeakPoint>,
         file_path: &str,
     ) -> Result<()> {
+        // Idris package manifest files (`.ipkg`) share the `idr`/`ipkg`
+        // extension family but are TOML-like build configs, not Idris
+        // source. They legitimately contain string-literal mentions of
+        // banned-pattern names (e.g. `brief = "...zero believe_me..."`)
+        // that would false-fire the substring-based ProofDrift detector
+        // below. Skip them entirely.
+        if file_path.ends_with(".ipkg") {
+            return Ok(());
+        }
         // Strip line ('--') and block ('{- -}') comments so that doc lines like
         // `||| no believe_me required` (which start with `--` after the bar
         // notation is normalised by lines()) and summary blocks do not produce

src/types.rs

@@ -73,6 +73,7 @@ pub enum Language {
     Shell,
     Julia,
     Lua,
+    Chapel,
 
     // === Nextgen custom DSLs ===
     WokeLang,
@@ -159,6 +160,7 @@ impl Language {
             "sh" | "bash" | "zsh" | "fish" => Language::Shell,
             "jl" => Language::Julia,
             "lua" | "luau" => Language::Lua,
+            "chpl" => Language::Chapel,
 
             // Nextgen custom DSLs
             "woke" => Language::WokeLang,
@@ -201,6 +203,7 @@ impl Language {
             Language::Shell => "shell",
             Language::Julia => "julia",
             Language::Lua => "lua",
+            Language::Chapel => "chapel",
             Language::Rust => "rust",
             Language::C | Language::Cpp => "c-family",
             Language::Go => "go",