Modules determine their own compatibility with the library

A module is built against the system-installed libdpm-core.so and is
responsible for being correct against it. Where it needs to act on the
version it is running under, dpm_core_version() reports that and the
module decides for itself.

dpm_module_core_min() is removed. It was a declaration handed to the
library to enforce on the module's behalf, and enforcement of that kind
belongs nowhere in a library that routes and hosts. The contract is now
three reserved symbols and load validation is two steps: the reserved
symbols resolve, and the version and description probes return
well-formed values.

compare_versions had no remaining caller and is removed; parse_version
stays for the well-formedness probe. The core_too_new fixture went with
the handshake it existed to exercise.

include/dpm/core.h

@@ -92,7 +92,6 @@ typedef struct dpm_module_info {
     const char* name;         /* module name (filename minus .so)      */
     const char* version;      /* module's own X.Y.Z                    */
     const char* description;  /* one-line description                  */
-    const char* core_min;     /* minimum libdpm-core version it supports */
 } dpm_module_info;
 
 /* ------------------------------------------------------------------ */
@@ -139,9 +138,9 @@ DPM_API void dpm_close(dpm_ctx* ctx);
  * context. Modules are loaded at most once per context; repeated
  * calls return the same handle.
  *
- * Version compatibility is the caller's judgement, not this library's:
- * read the loaded module's version with dpm_module_info_of() and
- * decide whether it is acceptable.
+ * Version compatibility is the caller's judgement: read the loaded
+ * module's version with dpm_module_info_of() and decide whether it is
+ * acceptable.
  *
  * @param ctx The libdpm-core context
  * @param name The module name (its filename minus .so)
@@ -151,13 +150,11 @@ DPM_API void dpm_close(dpm_ctx* ctx);
 DPM_API dpm_module* dpm_require(dpm_ctx* ctx, const char* name);
 
 /**
- * @brief Reports what libdpm-core sees in a loaded module
+ * @brief Reports what the library sees in a loaded module
  *
- * Fills `out` with the module's name, version, description, and
- * minimum-libdpm-core version, exactly as they were read at load. No
- * compatibility conclusion is drawn from these values; the caller
- * decides whether the version it is looking at is too new or too
- * old for its purposes.
+ * Fills `out` with the module's name, version, and description,
+ * exactly as they were read at load. The caller decides whether the
+ * version it is looking at suits its purposes.
  *
  * @param ctx The libdpm-core context
  * @param mod A module handle from dpm_require()
@@ -210,9 +207,8 @@ DPM_API dpm_cursor* dpm_list_modules(dpm_ctx* ctx);
 /**
  * @brief Advances an enumeration cursor
  *
- * Fills `out` with the next module's name, version, description, and
- * minimum-libdpm-core version; the string pointers remain valid until
- * context close.
+ * Fills `out` with the next module's name, version, and description;
+ * the string pointers remain valid until context close.
  *
  * @param cur The cursor from dpm_list_modules()
  * @param out Receives the next module's information
@@ -296,11 +292,17 @@ DPM_API const char* dpm_last_error(dpm_ctx* ctx);
  *                                  int argc, char** argv);
  *   const char* dpm_module_version(void);
  *   const char* dpm_module_description(void);
- *   const char* dpm_module_core_min(void);
  *
  * dpm_module_execute is the module's entire functional surface; its
  * capabilities are addressed by command string, so a module publishes
  * no headers, struct layouts, or symbols to anything that calls it.
+ *
+ * A module determines for itself whether it can work with the library
+ * it is running against: dpm_core_version() reports the running
+ * version, and the module proceeds or fails on its own judgement. A
+ * module is built against the system-installed libdpm-core.so and is
+ * responsible for being correct against it.
+ *
  * The library refuses to load any module that does not validate
  * completely (see the DPM specification: load-time enforcement).
  */

include/internal/modules.hpp

@@ -34,7 +34,6 @@ struct dpm_module {
     void*       handle = nullptr;
     std::string version;
     std::string description;
-    std::string core_min;
     int (*execute)(dpm_ctx*, const char*, int, char**) = nullptr;
 };
 

include/internal/version.hpp

@@ -1,6 +1,6 @@
 /**
  * @file version.hpp
- * @brief X.Y.Z version parsing and comparison
+ * @brief X.Y.Z version parsing
  *
  * @copyright Copyright (c) 2026 SILO GROUP LLC
  * @author Chris Punches <chris.punches@silogroup.org>
@@ -33,13 +33,4 @@ namespace dpmcore {
  */
 bool parse_version(const char* s, long out[3]);
 
-/**
- * @brief Compares two valid X.Y.Z version strings
- *
- * @param a First version
- * @param b Second version
- * @return -1 if a < b, 0 if equal, 1 if a > b
- */
-int compare_versions(const char* a, const char* b);
-
 } // namespace dpmcore