Fix hard fault: move .dmod.inputs/.dmod.outputs inside .data to fix startup copy

The startup data copy in startup.s copies bytes linearly from ROM
(__data_init_start__) to RAM (__data_start__ → __data_end__). Previously,
dmod-system.ld was included between .data and __data_end__, creating .inputs
and .outputs as separate sections with "> ram AT > rom". The ". = ALIGN(16)"
in dmod-system.ld only advances the VMA (RAM) location counter, creating
0–12 byte alignment gaps in RAM that have no corresponding gaps in the ROM
layout. This caused the startup copy to misplace the .inputs bytes in RAM,
corrupting the Dmod_ApiRegistration_t entries (swapping .Function/.Signature
pointers or mixing entries from adjacent registrations). The corrupted
.Function value (e.g. 0xd3aefbda) was then used to "connect" the module's
Dmod_EnterCritical output pointer, triggering a hard fault at runtime.

Fix: inline the .dmod.inputs and .dmod.outputs content directly inside the
.data section in linker/common.ld. Alignment padding inside a single section
is inserted identically in both the VMA and LMA representations, so the
startup byte-for-byte copy correctly initialises both sub-sections in RAM.

Co-authored-by: JohnAmadis <17320783+JohnAmadis@users.noreply.github.com>

Author: Copilot

linker/common.ld

@@ -149,9 +149,40 @@ SECTIONS
       . = ALIGN(4);
       *(.data .data.* .gnu.linkonce.d.*)
 
-   } > ram AT > rom
+      /*
+       * Include DMOD input/output sections inside .data so that the startup
+       * data copy (from __data_init_start__ to __data_end__) correctly handles
+       * them.  Placing these sections outside .data with "> ram AT > rom" would
+       * create VMA alignment gaps (the ". = ALIGN(16)" below) that have no
+       * corresponding LMA gaps, causing the startup copy to corrupt the .inputs
+       * section and produce garbage function-pointer values at runtime
+       * (e.g. Dmod_EnterCritical = 0xd3aefbda → hard fault).
+       *
+       * When the subsections live inside a single .data section the linker
+       * inserts the same alignment padding in both the VMA (RAM) and LMA (ROM)
+       * representations of the section, so the byte-for-byte startup copy
+       * remains correct.
+       */
+
+      . = ALIGN(16);
+      __inputs_start = .;
+      PROVIDE(__dmod_inputs_start = .);
+      KEEP(*(.dmod.inputs))
+      __inputs_end = .;
+      PROVIDE(__dmod_inputs_end = .);
+      __inputs_size = __inputs_end - __inputs_start;
+      PROVIDE(__dmod_inputs_size = __inputs_end - __inputs_start);
+
+      . = ALIGN(16);
+      __outputs_start = .;
+      PROVIDE(__dmod_outputs_start = .);
+      KEEP(*(.dmod.outputs))
+      __outputs_end = .;
+      PROVIDE(__dmod_outputs_end = .);
+      __outputs_size = __outputs_end - __outputs_start;
+      PROVIDE(__dmod_outputs_size = __outputs_end - __outputs_start);
 
-   INCLUDE dmod-system.ld
+   } > ram AT > rom
 
    . = ALIGN(4);
    __data_end__ = .;