feat: implement `genesis packages` command suite

[harry-hov]

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Adds gnoland genesis packages ... command to manipulates the addpkg txs in genesis.json

add    adds new package(s) from given dir(s)
clear  clears all the addpkg transactions
list   list pkgpaths of all the addpkg transactions
get    get the addpkg transactions for given package path(s)
del    deletes the given addpkg transaction(s)

Related: #1952

Contributors' checklist...

• [ ] Added new tests, or not needed, or not feasible
• [ ] Provided an example (e.g. screenshot) to aid review or the PR is self-explanatory
• [ ] Updated the official documentation or not needed
• [ ] No breaking changes were made, or a BREAKING CHANGE: xxx message was included in the description
• [ ] Added references to related issues and PRs
• [ ] Provided any useful hints for running manual tests
• [ ] Added new benchmarks to generated graphs, if any. More info here.

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 76.25000% with 19 lines in your changes are missing coverage. Please review.

Project coverage is 48.40%. Comparing base (edb321f) to head (9d788e8).

Files	Patch %	Lines
gno.land/pkg/gnoland/genesis.go	0.00%	7 Missing :warning:
gno.land/cmd/gnoland/genesis_txs_add.go	58.33%	2 Missing and 3 partials :warning:
gno.land/cmd/gnoland/genesis_txs_generate.go	86.20%	2 Missing and 2 partials :warning:
gno.land/cmd/gnoland/genesis_txs_clear.go	92.85%	1 Missing and 1 partial :warning:
gno.land/pkg/integration/testing_node.go	0.00%	1 Missing :warning:

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #1988      +/-   ##
==========================================
- Coverage   54.64%   48.40%   -6.25%     
==========================================
  Files         578      411     -167     
  Lines       77870    62408   -15462     
==========================================
- Hits        42551    30207   -12344     
+ Misses      32149    29684    -2465     
+ Partials     3170     2517     -653     

Flag	Coverage Δ
contribs/gnodev	?
contribs/gnofaucet	?
contribs/gnokeykc	?
contribs/gnomd	?
gno.land	61.97% <76.25%> (+0.33%)	:arrow_up:
gnovm	?
misc/autocounterd	?
misc/genproto	?
misc/genstd	?
misc/goscan	?
misc/logos	?
misc/loop	?
tm2	?

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[harry-hov]

@zivkovicmilos I have applied the changes as requested

Added these subcommands to genesis txs:

generate  generates addpkg txs from dir and add them to genesis.json
clear     clears all the transactions from the genesis.json

[zivkovicmilos]

Closing in favor of https://github.com/gnolang/gno/pull/2327