Add/Improve Debugging Features

[AlexanderViand-Intel]

Ideas/Tasks around improving the ability of developers to debug the programs they write using HEIR.

• Plaintext Execution Mode (i.e., run only arithmetization, then run resulting program in plaintext space Z_p, as discussed in the last office hours)
• "Decrypt-after-each" mode (kind of automating a common form of "printf() debugging")
  • add secret_key as argument for eval
  • after each HE operation (or maybe at granularity of each secret.generic after secret-distribute-generic?), decrypt the resulting ciphertext.
  • compare the decrypted result with the expected plaintext result
  • Report any deviations
• Improve Error/Warning Messages in HEIR through more meaningful Op "location" #1143

[ZenithalHourlyRate]

• "Decrypt-after-each" mode

As a side note, in my branch I hacked to get these things work.

• Sed to add secret_key as arg

sed -i 's/(CryptoContextT/(PrivateKeyT secretKey, CryptoContextT/g' func.h func.cpp

• after each HE operation

insert custom function call (used for speculating noise) after each openfhe eval op in heir-translate

https://github.com/ZenithalHourlyRate/heir/blob/06b929fa16809d33c0dfd8a911e2fd7f04e19660/lib/Target/OpenFhePke/OpenFhePkeEmitter.cpp#L205-L219

I was thinking about upstreaming them but did not find a proper dialect to put those custom func call. Maybe we can add a pass to insert func.call @external_func where the external func name comes from command line but then the function signature becomes a problem.