unoptimizable-recursion misses self-recursion written by plain name (Φ.<name>)

Problem

unoptimizable-recursion misses the most common way to write a self-recursive call — by plain name — because the modern parser resolves such calls to Φ.<name>, while the lint only looks for ξ.ρ.<name> (the ^-style form).

Root cause

src/main/resources/org/eolang/lints/design/unoptimizable-recursion.xsl:64-66:

<xsl:variable name="self" select="concat('ξ.ρ.', @name)"/>
<xsl:variable name="calls" select="... //o[@base = $self] ..."/>

Verified with a real program:

[] > calc
  if. > @
    n.eq 0
    1
    n.mul (calc (n.sub 1))

The inner call calc (...) is resolved by eo-parser 0.63.0 to @base='Φ.calc', so the lint finds no ξ.ρ.calc and reports nothing. The same recursion written as ^.calc does produce ξ.ρ.calc and is caught — so the lint's behavior depends on how the recursion is spelled, not on the recursion itself.

Expected behavior

Self-calls should be detected for both Φ.<name> and ξ.ρ.<name> forms (and ideally $<name>), so the lint is consistent regardless of the referencing syntax.

Related

• #1321 (compiler fails to convert certain self-recursion shapes into Java loops) — the underlying design issue.
• packs/single/unoptimizable-recursion/ — existing packs use the ^ form only.

Start at src/main/resources/org/eolang/lints/design/unoptimizable-recursion.xsl:64-66 and inspect the existing cases under packs/single/unoptimizable-recursion/. Run the related lint checks with examples using plain-name and ^ self-calls; done means both Φ. and ξ.ρ. forms are detected consistently, with coverage for the supported recursion references.