mssql-odbc: SQLBindCol/SQLBindParameter leave stale ARD/APD length/precision/scale behind on a differently-shaped rebind

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## Context

Follow-up from [PR #436](https://github.com/microsoft/mssql-rs/pull/436) ([AB#47437](https://sqlclientdrivers.visualstudio.com/b95cf060-8083-439d-8ef1-405d5bf219d8/_workitems/edit/47437) — descriptor records as the binding/metadata source of truth), flagged by an automated code review's non-blocking question.

## Problem

`ColumnBinding::write_to_record` (ARD, `SQLBindCol`) and the APD half of `BoundParam::write_to_records` (`SQLBindParameter`) only write `SQL_DESC_CONCISE_TYPE`, `SQL_DESC_DATETIME_INTERVAL_CODE`, `SQL_DESC_DATA_PTR`, `SQL_DESC_OCTET_LENGTH`, `SQL_DESC_INDICATOR_PTR`, and `SQL_DESC_OCTET_LENGTH_PTR`. Neither touches `SQL_DESC_LENGTH`, `SQL_DESC_PRECISION`, or `SQL_DESC_SCALE` on that record.

Sequence that reproduces the gap:
1. `SQLBindCol`/`SQLBindParameter` binds ordinal N with a C type whose precision/scale get set to some value.
2. A later `SQLBindCol`/`SQLBindParameter` call rebinds the *same* ordinal to a different C type.
3. `SQLGetDescField`/`SQLGetDescRecW` on `SQL_DESC_LENGTH`/`SQL_DESC_PRECISION`/`SQL_DESC_SCALE` for that record still reports the *previous* binding's value, not a value appropriate to the new C type.

This is metadata-introspection only — execution reads parameter type/size from the IPD (which *is* fully reset on every `SQLBindParameter`; `write_to_records` sets `precision`/`length`/`scale` unconditionally there) and reads column data via the ARD's `concise_type`/`data_ptr`/lengths (also unaffected). No query result or parameter value is wrong; only a direct `SQLGetDescField`/`SQLGetDescRecW` read of those three specific APD/ARD fields after a differently-shaped rebind can observe stale data.

## Verified against msodbcsql

`sqlcdesc.cpp`'s `SetADRec` (`SQLBindCol`/`SQLSetDescRec`, ~line 2615) and `SetADRecBP` (`SQLBindParameter`'s APD write, ~line 2789) both `ZeroMemory` the *entire* bind-info record before repopulating it, then call `SetTypeDefaults` (~line 12344) — a large per-C-type default table (GUID → `SQL_PREC_GUID`, NUMERIC/DECIMAL → `SQL_PREC_NUMERIC` + scale 0, FLOAT/REAL → their own distinct precisions, CHAR/VARCHAR/BINARY family → precision 1, date/time/timestamp/interval types → precision 2 and type-specific scales like `SCALE_DATETIME2`/`SCALE_TIME`/`SCALE_DATETIMEOFFSET`, interval-to-second subtypes → scale 6, etc.) — before writing any of the call's own arguments. `ExportImp::SQLBindCol` (~line 2470) computes this same default table itself (it has no precision/scale parameters of its own) and threads the result through to `SetADRec`. Net effect: msodbcsql always resets these three fields to fresh, C-type-appropriate defaults on every bind call, never leaving a prior binding's values behind.

## Why this wasn't fixed directly in #436

Correctly replicating `SetTypeDefaults` requires enumerating and verifying msodbcsql's full per-`SQL_C_*`-type default precision/scale table against this driver's own type constants — a self-contained, correctness-sensitive piece of work in its own right, not a one-line fix, and not worth rushing into an already large PR for a metadata-only edge case the reviewer who found it explicitly flagged as "not worth holding the PR for."

## Suggested approach

Add a `reset_type_defaults(c_type: SqlSmallInt) -> (length, precision, scale)` helper (or similar) mirroring `SetTypeDefaults`'s table, called from both `ColumnBinding::write_to_record` and the APD half of `BoundParam::write_to_records` before the other fields are written, with unit tests pinning at least one representative case per table branch (GUID, NUMERIC/DECIMAL, FLOAT, REAL, CHAR/VARCHAR/BINARY family, each datetime/interval subtype).

## References

- PR: https://github.com/microsoft/mssql-rs/pull/436
- Review: https://github.com/microsoft/mssql-rs/pull/436#pullrequestreview-5088111197
- Related work item: [AB#47437](https://sqlclientdrivers.visualstudio.com/b95cf060-8083-439d-8ef1-405d5bf219d8/_workitems/edit/47437)

Locate ColumnBinding::write_to_record and BoundParam::write_to_records, then trace the SQLBindCol and SQLBindParameter entry points and existing descriptor tests. Compare the C-type defaults needed for ARD/APD records and add coverage for each listed type-table branch. Done means differently shaped rebinds expose fresh length, precision, and scale values through SQLGetDescField and SQLGetDescRecW.

Written by the indexing model from the issue text.