Feat: Add tracing data to prelogin and login7 packets

[shueybubbles]

Fixes #226 .
I'm not ready to figure out how to maintain a sequence number update across redirects; there's not a clear place to store it.
I plan to have at least one more push to implement a Log method on tdsSession that prepends the activity id and the connection id to all the session-specific driver trace messages. I want to replace code like this:

if c.sess.logFlags&logRetries != 0 {	c.sess.logger.Log(ctx, msdsn.LogRetries, err.Error()) } 

with this:

c.sess.Log(ctx, msdsn.LogRetries, err.Error()) 

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 88.70968% with 14 lines in your changes missing coverage. Please review.

Project coverage is 74.85%. Comparing base (2521238) to head (2bff9dd).
Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
tds.go	72.00%	5 Missing and 2 partials ⚠️
session.go	94.28%	4 Missing ⚠️
bulkcopy.go	0.00%	1 Missing ⚠️
mssql.go	91.66%	1 Missing ⚠️
token.go	93.75%	1 Missing ⚠️

Additional details and impacted files

@@ Coverage Diff @@ ## main #228 +/- ## ========================================== + Coverage 74.45% 74.85% +0.39%  ========================================== Files 32 32 Lines 6397 6410 +13 ========================================== + Hits 4763 4798 +35  + Misses 1352 1327 -25  - Partials 282 285 +3 

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[apoorvdeshmukh]

Looks Good! Thanks for fixing the tests.