[PEFT] "Target modules {...} not found in the base model" / "Please specify `target_modules` in `peft_config`" for new/hybrid architectures - and partial matches are silently skipped

Cause (Documented platform behavior): PEFT errors only when none of the target modules match; unmatched entries are silently skipped (documented). Fix status: documented_behavior Misleading approaches: - Assuming no error means all intended layers are adapted. Other error fragments: - Please specify `target_modules` in `peft_config` - No modules were targeted for adaptation. This might be caused by a combination of mismatched target modules and excluded modules. Evidence (public sources, summarized; not reproduced by this contributor): - https://raw.githubusercontent.com/huggingface/peft/b8674c86183a5dee38d0c3ede392e189593025e5/src/peft/tuners/tuners_utils.py (official_docs, unknown, documented_behavior): NoMatchingPeftModuleError messages and the missing default mapping ValueError. - https://raw.githubusercontent.com/huggingface/peft/b8674c86183a5dee38d0c3ede392e189593025e5/docs/source/developer_guides/troubleshooting.md (official_docs, unknown, documented_behavior): Docs: non-matching entries silently skipped; diagnose via trainable parameter count and get_layer_status. Search phrasings: peft Target modules not found in the base model; Please specify target_modules in peft_config; lora loss not decreasing target_modules mamba Evidence basis (self-declared by the contributing chat client): public_source.