.Localize method does not get entire string if it is split across lines

[tombogle]

See sillsdev/libpalaso#1173 for an example.

[imnasnainaec]

Claude fix summary:

Affected file: src/L10NSharp/CodeReader/StringExtractor.cs (lines 423–442)
Method: GetParameters

Root cause: The IL-walking GetParameters method handles Ldstr (load string) opcodes but does not reconstruct strings concatenated with + across source lines. The C# compiler emits multiple Ldstr instructions followed by a String.Concat call. The opcode loop has two branches — one for Ldstr (line 429) and an else if for non-Call opcodes (line 431); a Call matches neither, so String.Concat is silently skipped and the individual Ldstr parts are never joined into one parameter.

Fix: When GetParameters encounters a Call to String.Concat, walk backward to collect all consecutive Ldstr operands, concatenate them in order, and return the combined value. Must handle both 2-arg and params-array String.Concat overloads.

Fix size: M | Review: Medium | Risk: Medium