fix(cdsl): recover split demat account summaries and broker names

[vmathur2004]

Summary

• reconstruct CDSL demat account summary rows when PDF extraction splits identifiers across four or five cells
• join broker-name fragments before the DP and client identifiers so names do not collapse to a trailing word such as LIMITED
• add regression tests for split account summaries and broker names

Validation

• 107 focused demat unit tests passed
• git diff --check passed

[codereverser]

Thanks for finding the issue and fixing it.