Replace generic catch(Exception) with specific exception types

[sfloess]

Part of #27: Improve Error Handling and Logging

Scope

Replace overly broad catch (Exception e) blocks with specific exception types to improve error differentiation and handling.

What to do

• Audit all catch (Exception e) blocks across the codebase
• Replace with specific catches: IOException, JsonParseException, HttpTimeoutException, InterruptedException, etc.
• Where multiple specific exceptions are needed, use multi-catch (catch (IOException | JsonException e))
• Only keep catch (Exception e) as a final fallback in top-level handlers where truly appropriate
• Log each exception type at the appropriate level

Acceptance criteria

• Broad catch (Exception e) blocks reduced by at least 80%
• Exception handling is specific enough to distinguish network errors from parse errors from config errors
• Each catch block has appropriate logging and recovery behavior