Spring <beans> XML extraction — connect XML-declared beans to Java classes and to each other (branch ready)

[ESPINS]

Legacy Spring / eGovFrame codebases declare beans in XML, so annotation-free classes look dead in the graph today: codegraph emits only a file node per Spring config XML (the MyBatis extractor correctly skips them as non-mapper).

This adds a lenient Spring <beans> extractor: <beans>-rooted XML (comment-aware root sniff; everything else keeps the MyBatis path untouched) emits bean nodes, an instantiates edge to the class= FQN — which is what finally connects a Java class to its XML bean — and bean→bean references (ref/idref/parent/depends-on/factory-bean/p:/c:-ref/method-injection, recursive through collections/inner beans, resolved cross-file by bean name incl. aliases).

Reference implementation on my fork — regex/stack-based like the MyBatis extractor, no new dependency, 56 inline tests:

https://github.com/ESPINS/codegraph/tree/feat/spring-beans-extractor

Validated on the public eGovFrame web sample (Apache-2.0): an annotation-free class (EgovSampleExcepHndlr) now shows its XML bean in the codegraph node trail; 3/3 in-repo instantiates resolved, 16/24 refs resolved (all 8 misses are documented blind spots — annotation-scanned beans etc.); non-Spring XML (pom/web.xml/log4j) unaffected; no node explosion. Documented v1 deferrals in-source: SpEL #{bean} refs, and the mapperLocations → mapper-file promotion that would complete the Spring↔MyBatis bridge.

Independent of #1209 (zero shared files — the branches apply cleanly in any order).

Pick / re-implement whatever's useful.

[ESPINS]

v1.1 is up on the same fork branch, adding three things on top of the extractor above:

1. Literal jobClass/targetClass-style property values (*Class/*ClassName name + FQN-shaped value) are promoted to instantiates refs — so Quartz JobDetailFactoryBean configs connect to their job classes.
2. ref="${prop:defaultBean}" placeholders resolve to their default bean name.
3. Dangling ref= names join to @Service/@Component/@Repository/@Controller(/@RestController)-annotated classes by derived name — only when exactly one unambiguous candidate exists, and the join stands down whenever an XML-declared bean of that name exists, so it can never override explicit config.

All three are silent-safe heuristics (a miss, never a wrong edge). 46 new inline tests on top of v1's; zero regressions on the public eGovFrame sample or the full 2,349-test suite.

Branch: https://github.com/ESPINS/codegraph/tree/feat/spring-beans-extractor — pick / re-implement whatever's useful.