adl/oct/seq: Create Component Unit `adl/oct/st/flat_dbm`

[flisboac]

A flat, non-coherent, difference-bound matrix. Accesses to elements are done in terms of octdiff_vexpr objects (or any other type that may be converted to it).

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Dependencies

• adl/oct: Create Module Unit adl/oct/st #33
• adl/oct: Create enum-value-related Component Units #31
• adl/oct: Create Component Unit adl/oct/dbm_info #36